Dishwasher with a heat pump

Abstract

A dishwasher (1) with at least one heat pump (14) is designed such that an air conveying device (26) can be operated for a run-on time period (NZ1, NZ2) after the end (tKA) of the last heating phase (AHK) for washing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the rinse phase (KP) of at least one dishwasher program (GP) to be carried out.

Description

[0001] The present invention relates to a dishwasher, in particular a household dishwasher, having at least one heat pump comprising at least one compressor, a condenser, an expansion element and an evaporator, which are connected to one another via line regions for conveying a working medium which changes its state of aggregation during operation, wherein the heat pump is assigned at least one supply line and one discharge line of washing liquid which can be circulated in the dishwasher, and wherein at least one air conveying device is provided.

[0002] It is known that in order to optimise the energy consumption of a dishwasher, in particular a household dishwasher, it is possible to equip the dishwasher with a heat pump in order to at least support the heating of the rinse water circulating in the dishwasher, i.e. to achieve this partially or, if the dishwasher, in particular its heat pump, completely via the heat pump,. Such a heat pump is preferably an air-to-heat pump. Its evaporator usually has an evaporator line which runs in meanders or windings and through which the working medium flows, and flat heat exchange elements, in particular so-called fins, which are thermally conductively connected to the evaporator line and between which channels or passages through which air can flow are provided. The structure orDuring a dishwashing program, ambient air is passed through the evaporator structure by means of an air conveying device during at least one heating phase of the dishwashing water carried out by the heat pump. The evaporator extracts heat from the ambient air and transfers this to the working medium of the heat pump flowing through its evaporator line. The heat pump's condenser then transfers heat from the working medium to the dishwashing water to be heated. The ambient air, which is forcibly fed to the evaporator by means of the air conveying device (often underneath kitchen units) during operation of the heat pump, cools as it flows through the structure.of the evaporator structure due to the removal of thermal energy, so that cold air, in particular at least temporarily with a temperature of less than 6°C (Celsius), preferably with a temperature around freezing point (0°C) or even below zero, leaves the heat pump and ultimately the dishwasher into the environment at the location where the dishwasher is installed. If this cold air then flows onto a building wall close to the dishwasher and / or an adjacent piece of kitchen furniture, there is a risk that the building wall and / or the piece of kitchen furniture will become too cold, at least on the top side, compared to the dew point temperature of the room air at the location where the dishwasher is installed.In particular, if the dishwasher is installed with its rear facing a building wall with only a small air gap, and the air conveying device, with the heat pump compressor running, blows ambient air through the evaporator structure in the depth direction and then blows the cooled air through an opening or outlet in the rear of the dishwasher's body onto the building wall behind it, there is a risk that the surface of the wall will become too cold. Another critical situation can be if the dishwasher is installed in the corner of a building, e.g. a kitchen. In this case, not only the rear building wall but also possibly the corner of the building wall and possibly also the side building wall next to the dishwasher can become too cold due to the air blown out of the rear of the appliance body while the heat pump is running.A building wall to the side of the dishwasher can cool down too much on its surface, especially if the air cooled by the evaporator during heat pump operation is not blown out at the back of the dishwasher, but through an opening in a side wall of the dishwasher's body adjacent to this side building wall. If the dishwasher is installed in a recess in a kitchen unit, e.g. between two kitchen base units, depending on where the exhaust opening is located in the body of the appliance - at the back or at the side - the back of the building wall and / or the piece of kitchen furniture to the left and / or right of the dishwasher can be exposed to the cold air flowing out of the dishwasher when the heat pump is in operation.As a result, moisture from the room air flowing into the cold surface area can condense on the surface area of ​​the building wall and / or kitchen unit wall exposed to this cooled air during heat pump operation, particularly after the heat pump has stopped operating, causing the building wall and / or kitchen unit wall to become damp. Due to the often poor ventilation in the rear and / or side areas of the dishwasher, the risk of mold growth is also high there.

[0003] It is known that the air flowing behind the dishwasher can be directed to a certain extent by means of air guide elements; however, the problem of wall cooling and poor wall ventilation remains unsolved.

[0004] The invention is based on the object of showing a way in which a dishwasher, in particular a household dishwasher, with a heat pump can always be operated flawlessly in practice under a variety of installation and / or mounting situations without impairments or even damage to surrounding building walls and / or furniture parts and / or to the dishwasher.

[0005] In particular, the invention I is based on the problem of improving the protection of a building wall and / or kitchen furniture wall located behind and / or next to the dishwasher in a heat pump for a dishwasher, in particular a household dishwasher.

[0006] The invention solves this problem by a dishwasher, in particular a household dishwasher, having the features of claim 1 and by a method having the features of claim 15. Regarding advantageous embodiments and further developments of the invention, reference is made to the further claims 2 to 14 and 16 to 21.

[0007] According to the invention, the air conveying device is operable for a follow-up period of a follow-up phase after the end of the last heating phase for dishwashing liquid carried out by means of the heat pump, in particular after the end of the final rinse phase, of at least one dishwashing program to be carried out, during which the dishwashing liquid used for cleaning dishes, glasses or similar items can be heated in at least one heating phase by means of the heat pump in one or more partial dishwashing phases. During the follow-up phase of the air conveying device, the compressor of the heat pump is switched off. The last heating phase carried out by means of the heat pump is the phase in which the heat pump is last involved, at least in part, in heating dishwashing liquid during the dishwashing phase of the respective dishwashing program to be carried out.The rinsing phase of the respective dishwashing program can comprise one or more successive partial rinsing phases - such as pre-rinsing, cleaning, intermediate rinsing and final rinsing.

[0008] The run-on phase, i.e. the ventilation phase of the air conveying device which follows the end of heat pump operation, advantageously ensures active ventilation of a building wall and / or kitchen furniture wall which is close to or adjacent to the dishwasher, in particular a household dishwasher, at its installation location or installation site and which was previously exposed to cold air cooled by the evaporator due to heat extraction during heat pump operation. This reduces the risk of moisture or condensation from the ambient air accumulating in one or more spots or areas of the building wall and / or kitchen furniture wall which have become cold during heat pump operation, which can be the case in particular if the room air is in the gap between the appliance body and the building wall and / or kitchen furniture wall which is close to it, i.e.is stationary, and as a result is cooled below its dew point temperature at these one or more cold wall spots or wall areas. If moisture or condensation from incoming, warmer room air has already condensed on the surfaces of these one or more cold spots or cold areas of the building wall and / or kitchen furniture wall, this moisture can be blown away from there by the air flow generated by the air conveying device during its after-run or ventilation operation and / or carried along (due to the higher mass transfer coefficient of air flowing past), and thus the surface of the building wall and / or kitchen wall can be dried out, i.e. made drier.

[0009] In particular, the building wall and / or kitchen unit wall to be ventilated is arranged behind and / or next to or to the side of the dishwasher, in particular a household dishwasher. It is in particular associated with a part of the appliance body of the dishwasher, in particular a household dishwasher, from which cold air flows out, in particular is blown out, during one or more heating phases for the dishwashing liquid carried out by the heat pump, i.e., during heat pump operation (compressor switched on) in the rinsing phase of the respective dishwashing program being carried out. As a result, it is directly or indirectly exposed to ambient air actively cooled by the evaporator.This particularly affects the building wall and / or kitchen furniture wall which is assigned to, preferably opposite, that part of the appliance body from which, during heat pump operation, air actively cooled by the evaporator is blown out via at least one outlet by means of an air conveying device of the dishwasher, in particular a household dishwasher, preferably by means of an air conveying device assigned to the evaporator for heat pump operation.

[0010] The one or more surface areas or regions of the building wall and / or kitchen furniture wall which, during the preceding heat pump operation, were exposed to cold air cooled by the evaporator due to heat extraction and which thus became cold, can, after the heat pump has been switched off, be supplied with warmer air (compared to the cold air during heat pump operation) by the after-running operation or ventilation operation of at least one air conveying device of the dishwasher, in particular a household dishwasher, and thus made warmer again.

[0011] According to an advantageous development of the invention, this warm air, which has a higher temperature than the cold air delivered by the dishwasher, in particular a household dishwasher, to the building wall and / or kitchen furniture wall during heat pump operation for heating up washing liquid, can in particular be ambient air which can be or is conveyed by at least one air conveying device of the dishwasher, in particular a household dishwasher, during the run-on phase from the environment around the dishwasher, in particular a household dishwasher, into the gap space present between the appliance body of the dishwasher, in particular a household dishwasher, and the building wall and / or kitchen furniture wall nearby thereto, and / or which flows in during the run-on phase due to the air movement brought about in the gap space by means of the air conveying device.In the gap space, in particular from the cold air located in front of the one or more cold surface spots or areas of the building wall and / or kitchen furniture wall and the warmer ambient air conveyed and / or flowing there, warmer, moving mixed air can form compared to the cold air, which heats the one or more cold surface spots or areas and absorbs and transports away any moisture present there.

[0012] According to an advantageous development of the invention, it can be particularly favorable if the building wall and / or kitchen furniture wall to be ventilated is able to be or is flowed through with ambient air in the after-running phase or ventilation phase by means of at least one air conveying device of the dishwasher, in particular a household dishwasher, which flows through a path or air conveying path, in particular an intake path, in the appliance body of the dishwasher, in particular a household dishwasher, and / or a path or air conveying path, in particular an intake path, which is in other thermal contact with the appliance body, along which it is passed through one or more waste heat or air conveying devices present there.Components of the dishwasher, in particular a household dishwasher, which give off waste heat can be preheated or are preheated, in particular to a temperature higher than the temperature of the ambient air outside the dishwasher, in particular a household dishwasher, around its installation or mounting location. These one or more components giving off waste heat are preferably components which were heated directly and / or indirectly with the aid of or at least with the support of the heat pump in one or more partial rinse phases of the rinse phase of the respective dishwashing program which preceded the after-run phase or ventilation phase and which, after the heat pump has been switched off at the end of the last heating phase for heating the rinse liquid of a respective dishwashing program, now give off heat ortransfer thermal energy - in particular heat passively due to their thermal mass - to the air flowing past. This can be, for example, the base of the washing tub, the pump sump, the circulating pump, ... , an additional electrical liquid heater that may be provided in addition to heating the washing liquid using a heat pump, which is then also switched off in the after-run phase, the condenser of the heat pump that is switched off in the after-run phase, the compressor of the heat pump that is switched off in the after-run phase, etc. In the after-run phase, heat can also be transferred to the air flowing past from one or more components that are still switched on in the after-run mode and give off thermal energy, in particular waste heat, such as, for example, the control / monitoring device of the dishwasher for carrying out the respective dishwashing program.

[0013] In particular, it can be advantageous if the at least one air conveying device extracts, in particular sucks in, air from a cavity or preheating chamber, in particular an intake chamber, in the appliance body for ventilating the building wall and / or kitchen furniture wall, during the follow-up phase, in which the air remained for some time after the end of the last heating phase for dishwashing liquid carried out by means of the heat pump until the start of the follow-up phase and was thus improved by one or more components releasing waste heat. This cavity, in particular an intake chamber, is expediently a section of the path orConveying path, in particular intake path, so that after the start of the run-on phase, the air conveying device conveys ambient air from outside the dishwasher, in particular a household dishwasher, into this cavity, in particular the intake chamber, of the appliance body, where it is preheated by one or more components that emit waste heat. The preheating chamber can preferably be located in the base support or plinth below the washing tub of the dishwasher, in particular a household dishwasher, and / or the air conveying path can preferably lead through the interior of the base support of the dishwasher, in particular a household dishwasher.

[0014] In terms of energy, it can therefore be particularly advantageous if at least one air conveying device of the dishwasher expediently conveys, in particular sucks in, air from the interior of the base support and / or along an air conveying path through the interior of the base support or appliance base of the dishwasher during the run-on phase. This is because one or more components present in the base support, such as the pump sump, the circulating pump, any electrical dishwashing liquid heater, the control / monitoring device for carrying out one or more dishwashing programs, the compressor of the heat pump, the condenser of the heat pump, etc., and / or one or more components adjacent to the base support, such asthe bottom wall of the washing container, which was / were heated and / or warmed up during the one or more washing liquid heating phases preceding the after-running phase by means of operation of the heat pump and / or any liquid heating system present, and / or are now in operation during the after-running phase, waste heat is transferred to the air conveyed, in particular sucked in, by the air conveying device before it leaves the appliance body of the dishwasher, in particular before it is blown out of the appliance body by the air conveying device.

[0015] According to an advantageous development of the invention, it can be particularly advantageous if, by means of the at least one air conveying device operated during the run-on phase, air is conveyed, in particular blown, through the structure of the evaporator during the run-on phase, during which the compressor of the heat pump is switched off, and the evaporator is largely dried. This reduces the risk of corrosion of the evaporator. However, without the run-on of the air conveying device after the end of the last heating phase for rinsing liquid carried out by the heat pump, in particular the final rinse phase, the evaporator could remain exposed to condensate or condensate water and / or frost and / or ice for too long, which could potentially lead to corrosion damage to the evaporator.

[0016] Advantageously, the air conveying device provided for the run-on phase is assigned to at least one evaporator of the heat pump. In particular, the air conveying device provided for the run-on phase or ventilation phase is formed by the air conveying device assigned to the evaporator for heat pump operation. The air conveyed by the air conveying device during the heat pump operation phase and the run-on phase is preferably ambient air, i.e., air from the space around the dishwasher.

[0017] If the air conveying device can be assigned or is assigned to the at least one evaporator and is suitable for conveying air from the space surrounding the dishwasher or ambient air through the structure of the evaporator and then out of the dishwasher, in particular via at least one air outlet provided in the appliance body - preferably at the rear thereof - out of the dishwasher, no additional air conveying device needs to be installed for the invention, but the air conveying device that is required anyway for the operation of the heat pump can be used.

[0018] According to an advantageous development of the invention, the air conveying device provided for the follow-up phase is arranged fluidically and in particular also spatially preferably in front of the evaporator, viewed in its air conveying direction.

[0019] Preferably, such an air conveying device, which is arranged in front of the evaporator and operated during the run-on phase or ventilation phase, draws in air (viewed in its air conveying direction) from an area - in particular the base support, above which the dishwasher's wash tub is arranged - during the run-on time of the run-on phase, in front of the evaporator, which is in particular accommodated in the base support, air which, as it passes or flows through its intake path, is heated to a temperature higher than the ambient temperature, i.e. higher than the temperature of the room air outside the household dishwasher, by waste heat or heat loss which is generated by one or more components of the dishwasher, such as the pump sump, wash tub base, condenser, compressor, control / monitoring device, etc.is released after the compressor of the heat pump has been switched off at the end of the last heating phase for rinsing liquid, which is carried out with at least partial support from the heat pump, in particular at the end of the final rinse phase, of the respective dishwashing program. This is because beforehand, thermal energy from the one or more previously carried out heating phases for rinsing liquid has been stored in some of these components, in particular in their thermal masses. Another part of these components, such as the electrical energy-consuming control / monitoring device which is provided for controlling the sequence of one or more dishwashing programs, can possibly also be in operation in the after-run phase and release waste heat to the passing air.The air, which is passively preheated in this way on its flow path upstream of the evaporator by waste heat from one or more components, is blown through the evaporator structure by means of the air conveying device, which is preferably arranged upstream of the evaporator, and in the process dries it more effectively, thereby reducing the risk of evaporator corrosion. Since the compressor has already been switched off before the after-run phase and remains switched off, and as a result the evaporator is no longer active during the after-run phase and therefore cools less or hardly any of the air flowing through its structure, which has been preheated by waste heat, this air can advantageously still be warm enough after leaving the dishwasher that it can heat the building wall it flows against and / or the kitchen furniture wall to a temperature preferably higher than the dew point temperature of the ambient air outside the dishwasher at its installation location or installation site.At least the air blown out of the dishwasher by means of the air conveying device during the run-on phase can cool the surface of a building wall and / or a kitchen unit wall, which previously became very cold in the respective dishwashing liquid heating phase while the heat pump was running (compressor is in operation) due to the air being greatly cooled by the then actively operated evaporator, in particular to below the dew point temperature of the ambient air, now during the run-on phase can be raised again to a temperature that is non-critical for condensation or the formation of condensate or even the associated formation of mold, which temperature is preferably above the dew point temperature of the ambient air outside the dishwasher.Any moisture on the surface of the building wall and / or the kitchen furniture wall can thus be more effectively removed during the run-on phase of the air conveying system by the draft generated by the exhaust air, which is warmer than the dew point temperature of the ambient air and preheated by waste heat.

[0020] In particular, the air conveying device is arranged downstream of the compressor in terms of its air conveying direction. This allows the compressor's waste heat to be transferred in an energetically efficient manner to the air drawn in by the air conveying device during the respective heat pump operating phase and, finally, after the end of the last rinse fluid heating phase carried out by the heat pump, in particular after the end of the final rinse phase, during the respective follow-up phase.

[0021] In summary, it is particularly advantageous for the active ventilation and drying of a building wall and / or kitchen furniture wall that is located in front of and / or next to the household dishwasher if the air conveying device that is assigned to the evaporator for heat extraction during the respective washing liquid heating phase is used for the after-running phase. This is because then no further air conveying device is required. If the intake path for the ambient air sucked in by this air conveying device during the ventilation phase leads past one or more components of the household dishwasher that previously absorbed thermal energy during the respective heating phase for the washing liquid and / or generate it during the after-running phase, the air sucked in by the air conveying device can now absorb waste heat orAbsorb waste heat from these one or more components and are then blown by the air conveying device as preheated air, in particular from the air outlet of the evaporator, into a gap space which lies between the household dishwasher and the building wall and / or kitchen furniture wall arranged behind it, and / or between the household dishwasher and the building wall and / or kitchen furniture wall arranged next to it, and / or are blown onto the building wall and / or kitchen furniture wall to be ventilated.

[0022] Furthermore, it may be expedient if the air outlet of the evaporator is fluidly connected to at least one air outlet in the appliance body of the dishwasher. In particular, the evaporator can be arranged such that its air outlet end terminates in the region of or in an outlet opening provided in the appliance body or protrudes slightly outward through it, so that the air leaving the evaporator can be discharged into the environment.

[0023] In the gap between the section of the appliance body having the at least one air outlet and the building wall and / or kitchen furniture wall adjacent to this area of ​​the appliance body, in particular the nearby building wall and / or kitchen furniture wall behind and / or next to the dishwasher, mixed air can be generated and moved, in particular circulated, from the air blown out of the air outlet by one or the air conveying device assigned to the evaporator, the ambient air present in the gap, and the room air drawn in by the air flow of the air blown out of the air outlet.In any case, after the end of the last heating phase of the dishwashing liquid carried out by means of the heat pump, in particular after the end of the final rinse phase of the respective dishwashing program to be carried out, by operating the air conveying device for the run-on time of a run-on phase, it is largely avoided that the air remains stagnant in the gap space for too long and the surface of the respective building wall and / or kitchen furniture wall which is or are assigned to the dishwasher, in particular the part of the appliance body of the dishwasher with the air outlet, remains too cold and possibly associated with it too humid for too long.This active ventilation through the run-on time phase of the air conveying device is accompanied by a targeted air exchange in the gap between the section of the appliance body having the at least one air outlet and the building wall and / or kitchen furniture wall closest to this area of ​​the appliance body, in particular the adjacent building wall and / or kitchen furniture wall behind and / or next to the dishwasher, by inflowing, warmer air from the room at the installation location or installation site of the dishwasher. The air flowing past the building wall and / or kitchen furniture wall takes moisture with it, so that any damp spots that may have formed on the surface of the building wall and / or kitchen furniture wall during operation of the heat pump (running compressor) during one or more previous dishwashing liquid heating phases and / or in the period thereafter can be dried out.

[0024] In particular, the air conveying device can preferably convey the ambient air it conveys into an area behind the dishwasher, diametrically opposed to the front of the dishwasher. There, the air can flow out, in particular, via at least one air outlet provided in the rear wall of the appliance body.

[0025] In particular, it may be advantageous if the evaporator of the heat pump is arranged in the base support of the dishwasher in such a way that its air outlet-side end is fluidly connected to at least one air outlet in the rear wall of the dishwasher, or terminates in this air outlet, or protrudes slightly outward from the appliance body through this outlet. The evaporator can preferably extend in the depth direction of the dishwasher, in particular essentially in a straight line, so that the air flows through its structure from front to back (relative to the spatial directions of the dishwasher in its operating position).

[0026] It may be particularly expedient if, in addition to the evaporator, the other components of the heat pump, such as the compressor, the condenser, the line areas or sections that connect these components of the heat pump to one another and carry the working medium of the heat pump, as well as the air conveying device assigned to the evaporator, are accommodated in the interior of the base support, above which the washing container of the dishwasher is arranged. The evaporator is preferably accommodated in the base support in such a way that during the respective after-run phase, the air conveying device, which is expediently arranged upstream of the evaporator in the air conveying direction, preheats air from the interior of the base support as well as the air flowing after it from the environment of the dishwasher using waste heat, which is then transferred to the base support and / or to components adjacent to it, such asThe water is released from the bottom of the washing tank, the pump sump, the circulation pump, the heat pump condenser, the heat pump compressor, the control / monitoring device for operating the dishwasher, etc.

[0027] It may be particularly expedient if the air conveying device provided for the follow-up operation is assigned a control unit that manages its operation, in particular determining and / or specifying the respective switch-on time, the running time, and / or the respective switch-off time of the respective follow-up phase of the air conveying device. This control unit can, in particular, be part of a control / monitoring device that supervises the operation of the heat pump. It and / or the latter can preferably be a subcomponent of a higher-level control / monitoring device by means of which the one or more partial rinsing phases, such as pre-rinsing, cleaning, intermediate rinsing, final rinsing, and the final drying phase of the respective dishwashing program, can be carried out automatically.The control / monitoring device, the control unit assigned to the heat pump, and / or the control unit assigned to the air conveying device can each be implemented by hardware and / or software components.

[0028] According to an advantageous development of the invention, the last rinse liquid heating phase carried out by means of the heat pump takes place during the final rinse phase of the respective dishwashing program. Its end preferably corresponds at least approximately to the end of the final rinse phase of the rinse phase of the respective dishwashing program, which phase consists of one or more partial rinse phases.

[0029] It can be particularly advantageous if the air conveying device simply continues to run, i.e. continues its operation, for a follow-on running period, in particular during the drying phase of the respective dishwashing program, after the end of the last heating phase for dishwashing liquid carried out by means of the heat pump, in particular after the end of the final rinse phase of the respective dishwashing program to be carried out, i.e. after the compressor of the heat pump has been switched off at the end of the heating phase. The compressor of the heat pump remains switched off during the follow-on running period. The air conveying device is in operation, in particular from the start of the last heating phase for the dishwashing liquid carried out by means of the heat pump, after which the compressor is switched off, - preferably continuously - until the end of the follow-on running phase.Such a - preferably uninterrupted - continuation of the operation of the air conveying device for a follow-up time after the end of the last heating phase for rinsing liquid carried out by means of the heat pump, in particular after the end of the final rinsing phase of the respective dishwashing program to be carried out, can be implemented very easily by the control unit of the dishwasher assigned to the air conveying device.

[0030] If necessary, the air flow rate of the air flow system during run-on operation can be reduced compared to the air flow rate of the air flow system when the heat pump is switched on, in order to avoid unnecessarily high energy consumption and / or unnecessary noise. If the air flow system has a fan, it may be expedient for the fan speed during the run-on phase to be different from the fan speed during the preceding rinse fluid heating phase, which was last carried out using heat pump operation. In particular, the fan speed during the run-on phase can be lower than the fan speed during the preceding rinse fluid heating phase, which was last carried out using the heat pump.

[0031] Alternatively, according to an advantageous development of the invention, it may be particularly favorable if the air conveying device can be switched on automatically after the end of the last heating phase for rinsing liquid carried out by means of the heat pump, in particular after the end of the final rinse phase, of the respective dishwashing program to be carried out, only with a time delay from this end, in particular in the drying phase of the dishwashing program, and can be operated for a follow-up time period, in particular until the end of the drying phase of the dishwashing program.

[0032] The air conveying device is therefore switched off after the end of the last heating phase for rinsing liquid carried out by means of the heat pump, in particular after the end of the final rinse phase, of the respective dishwashing program to be carried out and is only switched on again after a dead time or pause time for the duration of a follow-up phase, in particular in the program-final drying phase of the respective dishwashing program to be carried out.

[0033] In particular, the dead time can be dimensioned such that water droplets that remain on the evaporator after the end of the preceding heat pump operation (e.g. due to condensation water forming in the air flowing past during heat pump operation and / or due to defrosting of frost that forms during heat pump operation) have sufficient time to drip downwards in sufficient quantities from the evaporator, e.g. into a collecting tray. This largely prevents the situation where, after the air conveying device is switched on, the air forced through the evaporator structure unintentionally entrains a large amount of moisture from the evaporator and transports it to the building wall and / or kitchen unit wall adjacent to the dishwasher, which is then blown by the air flowing out of the dishwasher body.

[0034] Because in a dishwasher with at least one heat pump an air conveying device, in particular the air conveying device provided for heat pump operation, can be automatically switched on for a follow-up operation or ventilation operation after the last heating phase for washing liquid of a dishwashing program to be carried out, carried out by means of the heat pump, in particular after the end of the final rinse phase, moisture can be blown away from an area between the dishwasher and a building wall and / or this space can be flowed through with air, preferably with air that is warmer (compared to heat pump operation), which absorbs any moisture present on the surface of the building wall and transports it away from the gap space present between the dishwasher and the building wall.

[0035] By waiting until the air flow system is switched on, it is also possible to ensure that heat energy from the dishwasher is released into the space between the dishwasher and an adjacent building wall and / or kitchen unit wall. This allows the temperature to be raised above the dew point of water before air is supplied by the air flow system when the heat pump is switched off, significantly reducing the risk of condensation and mold growth even when air is supplied at this time.

[0036] Furthermore, the air flow system, in particular its fan, emits no noise during the waiting time until the air flow system is switched on, which is beneficial for the noise emission of the household dishwasher relative to the total running time of the respective dishwashing program. This applies in particular if the post-run operation takes place during the drying phase and / or during a subsequent storage phase ("storage function"), and the duration of the drying phase and / or the duration of the storage phase are / is added to the total running time of the dishwashing program.

[0037] If the air conveying device, in particular the air conveying device provided in heat pump operation for flowing ambient air through the structure of the evaporator, can be switched on and operated without the heat pump being operated at least outside of the rinsing phase of the respective dishwashing program, i.e. after the end of one or more partial rinsing phases, in particular the final rinse phase, of the respective dishwashing program, the air conveying device can run on its own during the after-run phase without water condensing on the evaporator or the evaporator even being cold or actively cooled during this time. The air conveyed by the air conveying device during the after-run phase is therefore ideally not actively cooled or loaded with water there, even if it overflows the evaporator or flows through its structure.

[0038] In particular, the air conveying device can be switched on at a time interval of at least 3 minutes, in particular from 3 minutes to 5 minutes, after the end of the last heating phase for rinsing liquid carried out by means of the heat pump, in particular after the end of the final rinse phase of the respective dishwashing program to be carried out, in order to thus already provide sufficient time for the dripping of condensate adhering in particular to the evaporator.

[0039] If necessary, i.e., under certain practical circumstances, it may be expedient for the air conveying system to be switched on at least 20 minutes after the end of the last heating phase for the dishwashing liquid carried out by the heat pump, particularly the final rinse phase. This allows sufficient time for the heat pump itself, in particular, to allow the evaporator to warm up sufficiently, in addition to allowing condensate to drip off, so that when the air conveying system is switched on, the building wall and / or the kitchen furniture wall are not exposed to moisture or cold air.

[0040] There may also be situations where it may be expedient to delay the air circulation system from being switched on until at least 40 minutes after the end of the last heating phase for the dishwashing liquid carried out by the heat pump, particularly the final rinse phase. In this case, the drying and heating of the building wall and / or kitchen unit wall, and / or the heat pump's evaporator, can continue until the air circulation system is switched on, allowing the aforementioned advantages to be further enhanced.

[0041] If the air conveying device is assigned to the at least one evaporator and is suitable for conveying air from the space surrounding the dishwasher through the structure of the evaporator and then out of the dishwasher, in particular via at least one air outlet provided in the appliance body - preferably at the rear thereof - no additional air conveying device needs to be installed for the invention, but rather the air conveying device that is already required for the operation of the heat pump can be used. In particular, the air conveying device can be assigned to the at least one evaporator and designed in such a way that it can convey ambient air through the structure of the evaporator, preferably into a rear area behind the dishwasher that is diametrically opposite the front of the dishwasher.

[0042] The air conveying device is preferably arranged upstream of the evaporator, viewed in its air conveying direction, and is assigned to the evaporator for the purpose of flowing ambient air around and / or through the evaporator. This allows ambient air to be drawn in and blown through the evaporator structure both during heat pump operation (when the compressor is operating) and during the run-on phase. Furthermore, it can simultaneously discharge the air flowing around the evaporator or through its structure from the dishwasher into the environment after leaving the evaporator. A single air conveying device is therefore sufficient.

[0043] If necessary, the air conveying device for the run-on or ventilation phase can also be formed by at least one existing air conveying device that is provided in and / or on the household dishwasher for a different function than the air conveying device assigned to the evaporator for flowing and / or passing ambient air during the respective wash liquid heating phase carried out by heat pump operation. Such a second, already existing air conveying device is preferably not arranged upstream of the evaporator, but at a different location on the household dishwasher. It ensures ventilation of the gap during the run-on or ventilation phase, either alone or, if necessary, in combination with the air conveying device arranged upstream of the evaporator.In particular, during the ventilation phase, they can be used to convey, in particular blow, ambient air that is and / or is preheated by one or more components of the household dishwasher that emit waste heat into the gap space and / or onto the one or more cold zones or areas of the building wall.

[0044] The same applies if, according to a further alternative, at least one air conveying device is provided specifically or separately for ventilation operation in addition to the air conveying device provided for heat pump operation in front of the evaporator, in particular at a different location than this.

[0045] If the air conveying device comprises a conveying wheel which can be rotated about an axis which is horizontal or at least almost horizontal in the operating position of the dishwasher, a horizontal air flow can be generated which is particularly effective in the lower region of the dishwasher, so that from there, the air conveyed by the air conveying device can be blown against the building wall adjacent to the dishwasher, preferably the rear wall, and there the air, which is warmer in particular than the cold air conveyed during heat pump operation, can rise from bottom to top.

[0046] If the air conveying device is suitable for conveying air against a building wall located behind the dishwasher in the operating position for a ventilation phase, the risk of mold can be significantly reduced, especially in this area.

[0047] If the switched-on operating time or run-on time of the air conveying device in run-on operation is at least 10 minutes, in particular between 20 minutes and 60 minutes, very thorough drying and a high degree of air exchange can be achieved in the area close to the wall, ie in the area of ​​a building wall and / or kitchen furniture wall adjacent to the dishwasher, in particular in the area of ​​a building wall and / or kitchen furniture wall behind the dishwasher and / or to the side of the dishwasher.

[0048] For optimization, the operating time of the air conveyor system in post-run mode can be conveniently set so that the post-run phase in the drying phase lasts until the end of the drying phase. If the drying phase includes a door opening phase with only a gap-like opening to assist drying, the post-run phase can end at the end of the door opening.

[0049] To ensure high energy efficiency and longevity of the unit, the operating time of the air conveying device in run-on mode should preferably be a maximum of 90 minutes without interruption.

[0050] If necessary, the air conveying capacity of the air conveying device in run-on mode can be reduced compared to the air conveying capacity of the air conveying device when the heat pump is switched on in order to avoid unnecessarily high energy consumption and / or unnecessary noise.

[0051] There are various ways to control or regulate the time interval until the air conveyor system is switched on and / or the running time or duration of the air conveyor system's run-on operation: On the one hand, the time until switching on can be preset.

[0052] Alternatively, the ambient temperature in the room (around the dishwasher) can be measured, for example, during the wash phase of the current dishwashing program and / or at the beginning of the wash phase and / or even before it. The higher the ambient temperature or room temperature, the shorter the time until the dishwasher switches on can be.

[0053] Thirdly, for example, a temperature can be measured at the evaporator at regular intervals, and this temperature can be used as an input parameter for monitoring, particularly regulating and / or controlling, the run-on time and / or duration of the run-on operation. Humidity measurement is also possible in addition or as an alternative.

[0054] In particular, in each of the three types mentioned, the run-on time and / or the time interval until the air conveying device for run-on operation is switched on is / is dimensioned in such a way that a building wall and / or kitchen furniture wall located behind and / or next to the dishwasher, on its surface which is directly or indirectly flowed over by the air flowing through the structure of the evaporator after flowing out of the dishwasher, in particular which is at the level of the evaporator in the area closest to it, is heated to a temperature above the dew point for water in order to be able to reliably prevent the formation of condensation on the building wall and / or kitchen furniture wall.

[0055] In order to adequately heat the building wall and / or kitchen unit wall between the wash phase of the respective dishwashing program, during which the wash cycle is implemented, and the time until the air conveying system is switched on for the after-run operation, the waste heat from the dishwasher after it has been switched off or after the heat pump has been switched off during the wash cycle may be sufficient. This eliminates the need for additional heating to reheat the building wall and / or kitchen unit wall, which had previously become cold during heat pump operation.

[0056] The invention further relates to a method for operating a dishwasher with at least one heat pump, which comprises at least one compressor, a condenser, an expansion element and an evaporator, which are connected to one another via line regions for conveying a working medium which changes its state of aggregation during operation, wherein at least one supply line and one discharge line of washing liquid which can be circulated in the dishwasher are assigned to the heat pump, and wherein at least one air conveying device is provided, which is characterized in that the air conveying device is arranged after the end of the last heating phase for washing liquid carried out by means of the heat pump, in particular after the end of the final rinse phase, of at least one dishwashing program to be carried out, during which, in one or more partial rinse phases, the air for cleaning dishes,Glasses or similar items, the respective rinsing liquid used is heated in at least one heating phase by means of the heat pump, and is operated for a follow-up time.

[0057] The air conveying system can be switched on and operated without the heat pump running, at least outside the rinse phase of the respective dishwashing program and thus outside the rinse cycle to be implemented, in particular after the end of the final rinse phase. In particular, the heat pump's compressor is switched off during the run-on phase.

[0058] As described above, this method allows and is advantageous for the air conveying system to be switched on at a certain time interval, particularly 3 to 5 minutes, after the end of the rinse cycle. This can ensure sufficient drainage of condensate and / or dew from the evaporator.

[0059] Advantageously, the duration of the run-on phase and / or the time interval that elapses between the end of the last heating phase for dishwashing liquid carried out by means of the heat pump, in particular between the end of the final rinse phase of the respective dishwashing program to be carried out and the start of the run-on phase of the air conveying device, can be dependent on a measured temperature of the ambient air in the room at the installation location or installation location of the dishwasher and / or dependent on a temperature measured in the vicinity of the building wall after the end of the wash cycle.

[0060] Further developments of the invention are set out in the subclaims.

[0061] The advantageous embodiments and further developments of the invention explained above and / or reproduced in the subclaims can be used individually or in any combination with one another - except, for example, in cases of clear dependencies or incompatible alternatives.

[0062] The invention and its advantageous developments and further developments as well as their advantages are explained in more detail below with reference to drawings.

[0063] They show, in a schematic principle sketch: Fig. 1 schematically shows a perspective view obliquely from the front of a household dishwasher shown here as an example, with a door that can be swung downwards and with a base or base support arranged below its washing container for receiving functional elements, in which components of a heat pump or heat pump arrangement for heating washing liquid during at least one partial washing phase of a dishwashing program to be carried out are additionally accommodated in a manner that is advantageous in terms of connection and space, Fig. 2 is a perspective view of a heat pump, drawn out for illustrative purposes only, in which the evaporator is located in the vicinity of a rear wall of the appliance body of the household dishwasher, Fig. 3 a drawn-out, schematic, side view of a domestic dishwasher standing in front of a building wall - such as the one from Fig. 1 - with a heat pump whose evaporator is located in the rear area of ​​the base support below the washing container of the household dishwasher, and Fig. 4 a time-temperature diagram in which the interior temperature in the washing compartment of the household dishwasher is recorded at the top and the temperature on the surface of the building-side rear wall behind the household dishwasher is recorded at the bottom during the washing phase and the subsequent drying phase of a respective dishwashing program to be carried out, and in which the temperature profile without a run-on phase of an air conveying device assigned to the evaporator of the heat pump is shown in dash-dotted lines and the temperature profile of a first and a second run-on operating mode of an air conveying device assigned to the heat pump is shown in solid lines.

[0064] Elements with the same function and mode of operation are provided with the same reference numerals in the figures.

[0065] In Fig. Figure 1 schematically illustrates a perspective view of a dishwasher 1, specifically a household dishwasher, as an example, without the invention being limited thereto. If appropriate, it is transferable to another household appliance, such as a washing machine or a washer-dryer, in which a liquid is to be heated in an energy-efficient manner using a heat pump.

[0066] The household dishwasher described below according to Fig. 1 has, as a component of a partially outwardly open or closed appliance body 5, a washing container 2 for holding items to be processed or items to be cleaned, such as dishes, pots, cutlery, glasses, cooking utensils, and the like. In the washing container 2, the items to be washed can be arranged, in particular held, for example in dish baskets 11, in particular in a lower dish basket and in an upper dish basket arranged at a height above this, and / or in a cutlery drawer 10. It can be acted upon by so-called washing liquor or washing water 24 by means of one or more washing liquid application devices, such as rotatable spray arms, rotatable or fixed spray nozzles, and / or other liquid distribution units in one or more partial washing phases of a respective dishwashing program to be carried out. The washing liquor or washing water 24Rinsing liquid 24 is preferably understood to mean fresh water and / or water circulating in particular during the rinsing operation of the household dishwasher 1, depending on the partial rinsing phase, with or without added cleaning agent, and / or rinse aid, and / or drying agent, which comes into contact with the items to be washed. The rinsing liquor or rinsing liquid 24 can additionally also be mixed to a greater or lesser extent with soiling from the ongoing rinsing operation, which is rinsed off the items to be cleaned during the execution of one or more partial rinsing phases - such as pre-rinsing, cleaning, intermediate rinsing, final rinsing - of a respective dishwashing program to be carried out. If necessary, rinsing liquid can also be used for the one or more partial rinsing phases of the respective dishwashing program to be carried out, which in at least one partial rinsing phase, such asThe rinse water was already used during the final rinse phase of a previous dishwashing program, but remained relatively clean, and was then stored in a tank as domestic water. In particular, the newly added dishwashing water to the household dishwasher may have previously passed through an ion exchanger or other softening device for softening, i.e., before being applied to the items to be washed.

[0067] The washing container 2 can, as in the exemplary embodiment here, have an at least substantially rectangular layout with a front loading opening facing a user (in the operating position of the household dishwasher 1), which can be closed by a front door 3. In the Fig. 1, the front side of the household dishwasher 1 facing the user, in particular its washing compartment 2, is provided with the reference symbol V. In this exemplary embodiment, a washing chamber for the items to be cleaned and / or dried is delimited by three vertical walls 13 and two horizontal walls 13 of the washing compartment 2 and by the front door 3 in its at least approximately vertically upright closed position. In detail, the washing compartment comprises a ceiling (top) and a floor (bottom) as horizontal walls. Adjacent to the front side V of the washing compartment 2 facing the user in the transverse direction Q is a left, at least approximately vertically upright side wall 13 to the left, and opposite this to the right is a right, at least approximately vertically upright side wall 13. They are connected to one another at the rear by an at least almost vertically upright rear wall 13.

[0068] The upper end of the front door or flap 3, by means of which the front loading opening of the washing container 2 can be closed at its front side V, can be pivoted forwards and downwards in this embodiment, preferably about a lower horizontal axis. This door 3 is in Fig. 1 in a partially open position and then inclined to the vertical. In its closed position, however, it is at least almost upright and is Fig. 1 For opening, the door can be pivoted forward and downward about a lower horizontal axis in the direction of arrow 4, so that in the fully open position (end-of-open position) it is at least almost horizontal. Other door movements, e.g., via a parallelogram or other multi-joint arrangement, are also possible.

[0069] The door can be provided with a decorative panel or door panel on the outside, ie on the front side facing a user. In the embodiment of Fig. 1, the front door 3 is provided with a decorative panel 6 on its outer or front side, which is vertical in the closed position and faces the user, in order to thereby experience a visual and / or haptic enhancement and / or adaptation to surrounding kitchen furniture.

[0070] When the front door 3 is in its at least almost vertical closing position, in the case of a so-called partially integrated or fully integrated household dishwasher 1, the front side of the front door 3 can form part of a kitchen front made up of adjacent kitchen units or, in the case of a stand-alone household dishwasher, can also be without reference to other units.

[0071] Alternatively, it is also possible to provide a door hinged laterally on a side wall of the rinsing container 2.

[0072] It is also possible to provide a rinsing container which is closed all around and has a loading opening at the top, which can preferably be closed with a door which is arranged essentially horizontally in its final closed position.

[0073] The household dishwasher 1 is shown here in the embodiment of Fig. 1 only as an example as a stand-alone or free-standing appliance on floor B, or as a so-called partially integrated appliance and installed on floor B within a recess between adjacent kitchen units below a kitchen worktop. In the latter case, the adjacent kitchen units and the kitchen worktop are in the Fig. 1 omitted for the sake of simplicity.

[0074] In the lower area of ​​the household dishwasher 1, in this embodiment, below its washing container 2, there is a base or a base support 12, in particular for accommodating functional elements, such as a circulation pump (not shown) for circulating the washing solution 24 in a circulation circuit and / or a drain pump (not shown) for pumping the washing solution 24 out of a pump sump fluidically connected to the washing container 2, and here in this embodiment also a heat pump or heat pump arrangement 14 designed and operating according to the functional principle according to the invention. This can be accommodated there in terms of space and connection technology. Fig. 1, this placement of the heat pump assembly 14 in the base support or base 12 is symbolized only by a dotted rectangle. However, depending on the design of the household dishwasher, placement of the heat pump assembly in the base is not mandatory, i.e., deviating from the advantageous embodiment of Fig. 1, the heat pump arrangement can also be arranged partially or completely outside the base 12, such as on the outside of a side wall and / or rear wall of the rinsing container 2.

[0075] The appliance body 5 of the household dishwasher 1 has here in the embodiment of Fig. 1 has two opposite side walls S. At the rear, a rear wall R is provided, which may also be perforated and preferably allows access to the evaporator 20 of the heat pump 14.

[0076] The movable door 3 is in the embodiment according to the Fig. 1 is assigned, for example, an outer, front panel 8 extending in the transverse or width direction Q of the household dishwasher 1, which can comprise displays and / or operating elements and then also serves as a display and / or operating panel. Preferably in the area of ​​its lower edge, as here in the embodiment of Fig. 1, an access opening 7 accessible from the front or front side for manually opening and / or closing the door 3 is expediently provided. This access opening 7 is provided here, for example, only in the transverse center region of the door 3, which, however, is not mandatory. An access opening 7 extending at least almost across the entire width of the household dishwasher, for example, over 50 to 60 centimeters in the transverse direction Q for a 60 cm wide household dishwasher, is also possible. As an alternative to such a partially integrated or "stand-alone", ieIn the case of a freestanding, free-standing household dishwasher whose front door has a control panel in its upper edge area with display and / or operating elements that are visible on the front when the front door is in the vertically closed position, the entire front of a so-called fully integrated household dishwasher can be covered by a cover or front panel, such as a kitchen furniture panel. With this door variant, the control and / or display elements of a control panel can be provided, for example, on the upper outer edge of the front door, so that the control and / or display elements are only visible and / or accessible to a user on the upper edge of the door when the front door is in the open position. Other door variants are of course also possible depending on the type of household dishwasher and / or the setup or installation conditions.

[0077] In the transverse direction Q, the dishwasher often has an extension of 45, 50, or 60 centimeters. In the depth direction from its front V to the rear, its extension is often also around 60 centimeters. These values ​​are not mandatory. Also, the household dishwasher 1 does not have to be Fig. 1 can not only stand directly on a floor B, but can also be installed higher on the floor board of a kitchen base unit or within another piece of kitchen furniture, or can be set up on a plinth or kitchen worktop at a height above floor B. In particular, the height above can be selected such that a user is required to make only a slight or no bending movement, e.g. when loading or unloading the dish baskets, in particular the lower dish basket, of the dishwasher, or when refilling rinse aid and / or cleaning agent into a dosing unit provided on the inside wall of the front door 3, when the front door 3 is brought into its at least approximately horizontal end-open position. The lower edge of the dishwasher 1 can then, in this installation or installation position raised above floor B, preferably lie approximately 40 to 110 centimeters above floor B.The vertical height (extension in the height direction H) of the household dishwasher 1 may also vary or be different depending on the type of construction and / or installation conditions.

[0078] Such a household dishwasher 1 is often arranged at a short horizontal distance in front of a building wall 27, so that a narrow gap or gap 28 exists between the rear of the appliance body 5 and the building wall 27. It can - e.g. when installed in a built-in niche between adjacent kitchen furniture such as kitchen furniture base cabinets - be covered above by a worktop, which further complicates the air exchange in this gap area 28 between the rear of the household dishwasher 1 and the rear building wall 27. A building wall can also be present next to or to the side of a side wall S of the appliance body 5 of the household dishwasher 1, e.g. if the household dishwasher is installed in a corner area of ​​a living space, in particular a kitchen room, which can make the air exchange in the rear gap 28 to the side even more difficult.In the gap area between the side wall S of the device body 5 and the side wall of the building nearby, air exchange can also be problematic.

[0079] The heat pump or heat pump arrangement 14 of the household dishwasher 1 is in the Fig. 2 is shown in an exemplary embodiment with its functional components as a compact structural unit. With its help, the washing liquid present in the circulation pump circuit or hydraulic circuit of the household dishwasher 1 during at least one liquid-carrying partial washing phase, such as the cleaning phase and / or the final rinse phase of a dishwashing program to be carried out, for which heating is required, and / or the washing liquid intended for circulating in the circulation pump circuit, for which heating is required, can be at least partially heated. This means that either the washing liquid, for which heating is required in the respective partial washing phase, is preheated by the heat pump to a preheating temperature and then subsequently by means of a liquid heater, such asa continuous flow heater to its desired final temperature, or the rinsing liquid is heated completely to its desired final temperature by the heat pump alone, which is particularly energy-efficient when running a so-called eco program or other energy-saving program.

[0080] In this exemplary embodiment, the heat pump 14 is, in particular, a compressor pump, i.e., it comprises a compressor 16, with which mechanical work can be performed on a working medium 17 circulating in the heat pump 14, such as a propane / butane mixture or R600a (isobutane). The compressor 16, in which the mechanical work is performed on the working medium 17, is electrically driven.

[0081] In addition to the compressor 16, the heat pump or heat pump arrangement 14 comprises as functional units - which may, but do not have to, be structural units - at least one condenser 18, an expansion device or an expansion element 19, for example an expansion valve or a capillary, and an evaporator 20. These functional units 16, 18, 19, 20 are interconnected via line regions or line sections 21 for the forwarding of the working medium 17, which changes its state of aggregation during operation. The working medium 17 flowing through the heat pump arrangement 14 during its operation (compressor 16 is switched on) is in the Fig. 2 is symbolized by a separately shown arrow, which also indicates its flow direction.

[0082] In addition to the components mentioned, the heat pump arrangement 14 expediently comprises at least one air conveying device 26 which, viewed in its air conveying direction, is arranged upstream of the evaporator 20 and is assigned to the latter, in particular for heat pump operation. The air conveying device 26 preferably has a fan or a blower. When the heat pump 14 is in operation, i.e. its compressor 16 is running, in order to heat this dishwashing liquid to a desired target temperature by means of the condenser 18 for or during a partial dishwashing phase, in particular the cleaning phase and / or final rinse phase, of the respective dishwashing program to be carried out, which requires the heating of the dishwashing liquid used or to be used for this purpose in at least one heating phase, the air conveying device 26 conveys, in particular blows, ambient air 32 through the structure orthe structure of the evaporator 20, here in the exemplary embodiment with a conveying direction from front to back to the rear wall R of the appliance body 5 of the household dishwasher 1. The structure of the evaporator 20 comprises sections, in particular meanders or loops, of an evaporator tube VR of the evaporator 20 through which the working medium 17 can flow or through which it flows, which sections run transversely to the air conveying direction from front to back, i.e. in the depth direction of the household dishwasher. Transversely, in particular perpendicularly, to these sections of the evaporator tube VR there are provided upright, flat heat exchange elements VL, in particular fins, which are each thermally conductively connected to the sections of the evaporator tube VR. The upright, flat heat exchange elements VL are arranged at transverse distances from one another and here extend in the depth direction of the household dishwasher 1, i.e. from front to back.As a result, an air duct or air passage is provided between each two transversely adjacent, upright heat exchange elements VL, which extends in the depth direction of the household dishwasher 1 and is crossed at predetermined intervals in the depth direction and here in particular also in the height direction by a section of the evaporator tube VR. The heat exchange elements VL are penetrated transversely to their longitudinal extent in the depth direction by the sections of the evaporator tube VR through which the working medium 17 can flow or through. In this way, by means of the air conveying device 26, ambient air 32 can be conveyed, in particular blown through, through the ducts or passages present between the heat exchange elements WL from front to rear to the rear wall R of the appliance body 5 of the household dishwasher 1.In this case, heat is extracted from the ambient air 32 by the sections of the evaporator tube VR and the heat exchange elements VL connected to them in a heat-conducting manner and transferred to the working medium 17. The air conveying device 26 is expediently arranged in this embodiment such that, during its ongoing operation, ambient air 32 from the space surrounding the dishwasher 1 is drawn in, for example, through front ventilation slots 31 and / or through gaps, cracks, recesses and / or openings in one or more walls of the base support orappliance base of the household dishwasher 1, flows over the compressor 16 arranged in front of the air conveying device 26 and is preheated by its waste heat, and is preferably blown backwards (in the depth direction of the dishwasher) to the evaporator 20 and flows along its one or more, preferably meandering, line regions or line sections through which the working medium 17 can flow or through and / or along the heat exchange elements VL protruding from these, in particular fins. Here in the exemplary embodiment, viewed along the air flow path effected by the air conveying device 26, the air conveying device 26 assigned to the evaporator 20 is therefore preferably positioned between the compressor 16 and the air inlet of the evaporator 20.The compressor 16, the air conveying device 26 arranged downstream of it, and the evaporator 20 are arranged in the base support 12, in particular in a preferably at least approximately straight line one behind the other in the depth direction of the household dishwasher. After passing through the structure of the evaporator 20, the ambient air 32' cooled in this way by the evaporator 20 is finally blown out by the air conveying device 26 arranged upstream of the evaporator 20 through a recess or opening, i.e. through an air outlet LA in the rear wall R of the appliance body 5, in particular in the rear wall R of the base support 12, of the household dishwasher 1, into the surroundings of the dishwasher, where it flows onto the building wall 27 arranged behind the dishwasher, in particular in the area of ​​the building wall 27 opposite the air outlet LA (see . Fig. 3).

[0083] The heat pump 14 is also assigned at least one supply line 22 and one discharge line 23 (shown unconnected here) for washing liquid 24 that can be or is circulating in the household dishwasher 1. The washing liquid 24 to be heated—e.g., from a circulation circuit, in particular a circulation pump circuit (not shown) of the household dishwasher 1—flows via the supply line 22 into the inlet of at least one heat transfer area 50, here in the exemplary embodiment in particular a line or pipe section, which is in thermal contact with the condenser 18 through which the working medium 17 can flow or through, in particular its condenser tubes, and flows through this heat transfer area 50. The washing liquid 24, heated by the condenser 18 during heat pump operation, leaves the outlet of the heat transfer area 50 via the discharge line 23.It is then fed back into the circulation circuit, in particular the circulation pump circuit, at an upstream point, such as, for example, preferably the wash chamber in the wash tub 2 belonging to the circulation circuit and / or a pump sump arranged under the floor of the wash tub. The condenser 18 and the heat transfer area 50 through which the wash liquid 24 can flow or through, here in particular a pipe section, together form a heat exchanger WT, in which, during ongoing operation of the heat pump 14 (with the compressor 16 switched on), heat is transferred from the working medium 17 to the wash liquid 24 flowing through the heat transfer area 50. The wash liquid 24 flowing through the heat transfer device WT is in the . Fig. 2 symbolized by a separately shown arrow.

[0084] In the heat exchanger WT, the flushing fluid 24 to be heated expediently passes through the heat transfer area, in particular the heat transfer line section or pipe section, 50 in countercurrent to the working medium 17 flowing through the condenser 18. In this way, an efficient, i.e., highly effective, transfer of the heat from the working medium 17 to the flushing fluid 24 is ensured in the heat exchanger WT.

[0085] Furthermore, the heat pump 14 is expediently assigned an electrical connection option 25. By means of the electrical connection option 25, in particular the electric motor of the compressor 16 for its operation and / or the air conveying device 39 for its operation can be supplied with electrical energy. In addition, the heat pump arrangement 14 can, in addition to the electrical connection option 25 and the connection option 22, 23 for the rinsing liquid 24, optionally comprise various sensors and a connection 25' for a communication interface, in particular for a data bus. The electrical connection 25 can - as shown in the Fig. 2 by way of example - in particular be part of an electrical / communication module 29, possibly also comprising one or more sensors and the communication interface connection 25', in particular a data bus connection. The operation of the electric drive motor of the compressor 16 and the air conveying device 26 can be monitored, in particular controlled and / or regulated, via the communication interface connection 25'. This is shown in the Fig. 2 by dash-dotted double arrows KV2 and KV3. This communication interface connection 25' can preferably receive communication signals from and / or send them to a control unit CO via one or more signaling connections, in particular via a data bus. The control unit CO is in the Fig. 2 is additionally shown in dash-dotted lines. The communication connection between it and the communication interface connection 25' is symbolized by a dash-dotted double arrow KV1. With the help of the control unit CO, the operation of the heat pump 14, in particular its compressor 16 and / or its air conveying device 26, can be monitored. The control unit CO can be directly assigned to the heat pump arrangement 14, in particular be a component of the electrical / communication module 29, or - as in the Fig. 2 - may be provided at a different location in the household dishwasher 1, particularly in its base support 12, separate from the heat pump assembly 14. It may preferably be a subcomponent of a higher-level control / monitoring device SCO, by means of which the one or more partial rinsing phases, such as pre-rinsing, cleaning, intermediate rinsing, final rinsing, and the final drying phase of a respective dishwashing program to be carried out, can be carried out automatically. The control unit CO and / or the control / monitoring device SCO may be implemented by hardware and / or software components.

[0086] This heat pump 14 can - as in Fig. 2 - form a modular (installation) unit. For this purpose, at least the essential components 16, 18, 19, 20, 21 of the heat pump 14 through which the working medium 17 flows, and in particular also the air conveying device 26 arranged upstream of the evaporator 20, the heat exchanger WT provided for heating the dishwashing liquid 24, and / or the electrical / communication module 29 can be mechanically fixedly arranged on a carrier unit 15 holding them, such as a carrier plate or a holding frame or rack, so that a modular and easy-to-assemble unit is formed. The essential functional components 16, 18, 19, 20, 21 of the heat pump 14 through which the working medium 17 flows can be pre-assembled on the carrier unit 15, filled with the working medium 17, and tested for function before installation in the dishwasher 1. In particular, the heat pump 14 can already be pre-assembled, i.e.Before being installed in the domestic dishwasher 1—here, in the base support 12—the components 16, 18, 19, 20, 21 carrying the working medium 17 must be checked for leaks. Particularly if the air conveying device 26, the electrical / communications module 29, and / or one or more sensors, such as temperature and / or humidity sensors, are also attached to the support unit 15, it may be advantageous to also check these components assigned to the heat pump arrangement 14 for proper functionality in advance.

[0087] During the one or more heating phases for washing liquid, which is or are carried out by means of the operation of the heat pump, ambient air 32 is sucked in from outside the domestic dishwasher 1 by means of the air conveying device 26 arranged upstream of the evaporator 20, blown through the structure of the evaporator 20 to transfer heat to the working medium 17, whereby the air flowing through the structure of the evaporator 20 is cooled, and then the ambient air 32' cooled by heat extraction from the evaporator 20 is blown out of the air outlet LA provided at the rear of the appliance body 5, so that it impinges on the nearby building wall 27 behind the domestic dishwasher 1. In particular, the cold air 32' blown out of the air outlet LA during heat pump operation can impinge on an area of ​​the building wall 27 opposite the air outlet LA.As a result, the surface of the building wall 27 is cooled in particular by the blown-out cold air 32'; but wherever the cold air 32' otherwise passes over the building wall 27, the latter is also cooled. This creates the risk that the surfaces of these one or more cold zones or areas of the building wall 27 will become damp. This could occur in particular after the air conveying device 26 is switched off at the end of heat pump operation, if the cold air 32' previously blown out into the gap 28 by the air conveying device 26 during heat pump operation is followed by warmer gap air from warmer areas of the gap 28 compared to the cold air 32', which has a higher moisture content, and / or by warmer ambient air from outside the gap 28, which has a higher moisture content.Water droplets could condense from the air then standing in front of these one or more cold zones as a result of its cooling on the one or more cold zones of the housing wall 27.

[0088] In order to avoid this, after the end of the last heating phase for rinsing liquid carried out by means of heat pump operation, in particular after the end of the final rinse phase, of the respective dishwashing program to be carried out, a follow-up phase is carried out by means of at least one air conveying device, ie a ventilation phase following the heat pump operating phase intended for heating up rinsing liquid, such as NP1 or NP2 (see Fig. 4). This follow-up phase serves to blow preferably warmer air 32'' (compared to the cold air 32') onto the rear building wall 27, in front of which the household dishwasher 1 is installed, or to induce air movement in the gap 28. This air flow can heat the one or more cold zones or areas on the building wall 27 and / or dry any moisture or condensation already present there.

[0089] For this purpose, it is particularly advantageous if the air conveying device 26, which is arranged in front of the evaporator 20 and is used for the respective rinsing liquid heating phase carried out by means of heat pump operation, in particular for the last heating phase carried out by means of the heat pump, such as AHK (see Fig. 4) was in operation, is now used for the run-on phase or ventilation phase, such as NP1 or NP2, i.e., is put into operation. No additional air conveying system is then required for the ventilation phase.

[0090] In this exemplary embodiment, the air conveying device 26 advantageously draws in ambient air 32 from outside the appliance body 5 of the household dishwasher 1, preferably along an intake path in the base support 12, which leads past one or more components of the household dishwasher 1 that emit waste heat or waste heat. In this exemplary embodiment, such a waste heat-emitting component is, in particular, the compressor 16, which is arranged upstream of the air conveying device 26 (as viewed in its air conveying direction). Additionally or independently, waste heat-emitting components can include, for example, the washing tub base, the pump sump, the circulation pump, etc., an additional electrical liquid heater that may be provided in addition to heating the dishwashing liquid by means of a heat pump, which is then also switched off during the run-on phase, the thermal mass of a stationary weight, the condenser of the heat pump, the compressor of which is switched off during the run-on phase, etc. In the run-on phase, heat can also be transferred to the air 32 sucked in by the running air conveying device 26 by one or more components that are still switched on during the run-on operation and release thermal energy, in particular waste heat, such as the control / monitoring device SCO for carrying out the respective dishwashing program. The preheated air 32 that is sucked in by the air conveying device 26 during the run-on phase has, in particular, a temperature higher than the ambient temperature outside the household dishwasher 1.

[0091] In particular, it may be advantageous if, as in this embodiment, the air conveying device 26 during the follow-up phase such as NP1 or NP2 (see Fig. 4) Air 32 is taken, in particular sucked in, from a cavity or preheating chamber, in particular intake chamber, in the device body 5 for ventilating the building wall 27 or the gap space 28, in which the air 32 remained for some time after the end of the last heating phase carried out by the heat pump, such as AHK for rinsing liquid, until the start, such as tLE1 or tLE2, of the follow-up phase, such as NP1 or NP2, and was thereby improved preheated by one or more components releasing waste heat. This cavity, in particular intake chamber, is expediently a section of the travel path or conveying path, in particular intake path, so that the air conveying device 26 after the start, such as at time tLE1 or tLE2, of the follow-up phase, such asNP1 or NP2, during which ambient air 32 is conveyed from outside the household dishwasher 1 into this cavity, in particular the intake chamber, of the appliance body, where it is preheated by one or more waste heat-emitting components. The preheating chamber can be arranged as shown in the exemplary embodiment (see in particular . Fig. 2, Fig. 3) preferably in the base support or base 12 below the washing container 2 of the household dishwasher 1 in front of the air conveying device 26 and the air conveying path can preferably lead through this preheating space in the interior of the base support 5.

[0092] Since the compressor 16 has already been switched off before the run-on phase, such as NP1 or NP2, and remains switched off, and as a result the evaporator 20 is no longer active during the run-on phase and therefore cools less or hardly the air 32 flowing through its structure, which has been preheated by waste heat, this air is advantageously still warm enough after leaving the household dishwasher 1 to heat the building wall 27 against which it flows to a temperature preferably higher than the dew point temperature of the moisture-containing air present in the gap 28, in particular after the end of the run-on phase.

[0093] If, as in this embodiment, after the end tKA of the last heating phase AHK carried out by means of the heat pump, in particular after the end of the final rinse phase KP, of the respective dishwashing program GP to be carried out, a waiting time or pause time such as P1 or P2 elapses or passes until the air conveying device 26 is switched on for the follow-up phase such as NP1 or NP2, condensate water droplets that hang on the evaporator 26 at the end of the last heating phase AHK carried out by means of the heat pump can advantageously drip down, for example, into a collecting tray, which is in the Fig. 2, Fig. 3 has been omitted for the sake of simplicity of the drawing. This dripping phase prevents the air 32, which is forcibly conveyed through the structure of the evaporator 26, from unintentionally entraining a large amount of moisture from the evaporator and transporting it to the building wall 27 or into the gap 28 after the air conveying device 26 has been switched on for the after-running phase such as NP1, NP2. Thus, immediately at the start of the respective after-running phase such as NP1 or NP2 of the air conveying device 26, sufficiently preheated ambient air 32'' can be blown out of the air outlet LA provided on the rear of the base support into the gap 28 or onto the building wall 27 behind the household dishwasher 1.

[0094] Because the air conveying device 26 provided for heat pump operation can be automatically switched on for a follow-up operation or ventilation operation at a time interval such as P1 or P2 from the last heating phase carried out by the heat pump, such as the AHK for dishwashing liquid of a respective dishwashing program GP, any moisture present in the one or more zones or areas of the building wall 27 that have become cold as a result of the previous heat pump operation can be absorbed and carried away by the preheated air 32'' flowing over them. The cold zones or areas on the surface of the building wall 27 are heated by the flow of the preheated air 32'' during the follow-up phase, in particular to a temperature that is higher than the dew point temperature of the air present in the gap space 28, in particular after the end of the follow-up phase.During the run-on phase, the air present in the gap space 28 can be a mixed air consisting of the gap space air present there, the preheated ambient air blown into the gap space 28 and any ambient air 32 flowing into the gap space 28 from outside.

[0095] By means of the waiting time or pause time such as P1 or P2 until the air conveying device 26 is switched on for the respective after-run phase such as NP1 or NP2, it can also be achieved that heat energy or waste heat from the household dishwasher 1 is released into the space 28 between the household dishwasher 1 and the building wall 27 behind it during the waiting time or dead time such as P1 or P2. This means that when the heat pump 14 is switched off (compressor 16 is switched off) before air 32 is supplied by the air conveying device 26, i.e. before it is switched on in after-run mode, the temperature can already be raised above the dew point of water, so that when the air is then supplied in after-run mode by the air conveying device 26, the risk of condensation and mold formation on the building wall 27 is significantly reduced.

[0096] In addition, the air conveying device 26 arranged upstream of the evaporator 20 conveys, in particular blows, preheated air 32 through the structure of the evaporator 20 during the run-on phase, such as NP1 or NP2, during which the compressor 16 of the heat pump 14 is switched off, largely dries the evaporator 20. This also reduces the risk of corrosion of the evaporator 20.

[0097] By means of the after-run phase such as NP1 or NP2 of the air conveying device 26, the preheated air 32'' blown into the gap 28 by it causes an air movement in the gap 28 between the rear of the appliance body 5 of the household dishwasher 1 and the building wall 27 in front of which the household dishwasher 1 is installed, which leads to a warming up of cold areas on the building wall 27 and / or the drying of any damp areas present there. If, on the other hand, the air in the gap 28 between the rear of the appliance body 5 of the household dishwasher 1 and the building wall 27 in front of which the household dishwasher 1 is installed were to stand still after the last heating phase AHK carried out with the participation of the heat pump 14, in particular after the end of the final rinse phase KP of the respective dishwashing program GP, there would be a risk of moisture stains and / or even mold formation.

[0098] Fig. 4 shows a time-temperature diagram in which, at the top, a profile TS of the interior temperature in the washing compartment 2 of the household dishwasher 1 and, further down, a profile TW of the temperature on the surface of the building wall 27 located behind the household dishwasher 1 during the washing phase SP and the subsequent drying phase TP of a respective dishwashing program GP are plotted as examples. The time t in seconds (abbreviated: sec) is plotted along the abscissa of the time-temperature diagram and the temperature T in degrees Celsius (abbreviated: °C) is plotted along the ordinate. In this embodiment, the washing phase SP preferably comprises, in chronological succession, a pre-wash phase VP, a cleaning phase RP, an intermediate wash phase ZP and a final rinse phase KP.During these partial wash phases VP, RP, ZP and KP in which washing liquid is supplied, corresponding partial wash cycles of a wash cycle are carried out before the drying cycle of the dishwashing program GP which takes place during the drying phase TP. The pre-wash phase VP begins with the start of the dishwashing program GP at time tVE = 0 sec. For this purpose, in the exemplary embodiment, fresh water is preferably introduced into the wash tub 2. This fresh water is stored in a storage tank or heat exchanger tank, for example on the outside of a side wall of the wash tub 2 and has reached an ambient temperature RT of approximately 21°C during its residence time there. The items to be cleaned are subjected to this water by one or more washing liquid application devices until the end of the pre-wash phase VP. The temperature TW of the building wall 27 behind the household dishwasher 1 is approximately room temperature RT of approximately 21°C. After the end of the pre-wash phase VP and any additional drying time,The cleaning phase RP starts at time tRE after at least partial pumping of the rinsing liquid from the household dishwasher 1. Fresh water is supplied to the rinsing tank 2 as required, and detergent is added to the water then present in the rinsing tank. In order to heat this rinsing liquid to a desired final cleaning temperature SRT of approximately 45 °C in this case during a heating phase AHP, the heat pump 14 is switched on at the start of the cleaning phase RP and operated until time tHA, at which the desired final cleaning temperature SRT of the rinsing liquid mixed with detergent is reached. The heat pump 14 is then deactivated, i.e. its compressor 16 and its air conveying device 26 are switched off.The washing liquid heated in this way by the heat pump 14 is circulated in the circulation circuit of the household dishwasher 1 for a post-wash phase NW until the end of the cleaning phase RP and distributed to the items to be washed by means of one or more washing liquid application devices. Since, in the heating phase AHR while the heat pump 14 is operating (compressor 16 is running), heat is extracted from the ambient air conveyed through the structure of the evaporator 20 by the air conveying device 26, the air is significantly cooled by the evaporator 20. The cold air 32' blown out of the rear air outlet LA of the household dishwasher 1 by the air conveying device 26 can temporarily reach temperatures around 0 °C or, as in this embodiment, below 0 °C. Accordingly, the building wall 27 arranged behind the household dishwasher 1, which is flowed through by the cold air 32', cools down.As the heating-up phase AHR progresses, the wall temperature TW rises by a few degrees Celsius - here up to approximately 4 °C - towards its end, since the air 32 sucked in by the air conveying device 26 is then slightly preheated by one or more components which then emit waste heat, such as the compressor 16. Since the heat pump 14, in particular its compressor 16, is switched off in the post-wash phase NW, the air sucked in by the air conveying device 26 continues to heat up due to the components emitting waste heat - here up to approximately 10 °C at the end of the cleaning phase RP at time tRA. After the washing liquid mixed with cleaning agent and with dirt particles or impurities detached from the wash items has been pumped out, an unheated intermediate washing phase ZP is carried out from time tZE, ie the compressor 16 of the heat pump 14 remains off.In the intermediate rinse phase ZP, the items to be washed are preferably exposed to fresh water newly introduced into the circulation circuit, in particular into the wash tub 2, of the household dishwasher 1, and any dirt and / or detergent residues are washed off the items to be washed. At the end of the intermediate rinse phase ZP, the rinse liquid is expediently partially or completely pumped out of the wash tub 2. This is followed at time tKE by the final rinse phase KP, which concludes the rinse cycle, for which water mixed with rinse aid, in particular fresh water, is applied to the items to be washed by means of one or more rinse liquid application devices. The rinse liquid, i.e. water mixed with rinse aid, is heated by the heat pump 14 to a desired target final temperature SKT - as in this case, for example, approximately 42 °C - from the start of the final rinse phase KP at time tKA to the end of the final rinse phase KP at time tKA.After the end of the final rinse phase KP or after the end of the last heating phase AHK carried out by the heat pump 14 at time tKA, the heat pump 14 is switched off, i.e. its compressor 16 and its air conveying device 26 are stopped or switched off respectively. Since the building wall 27 is supplied with cold air 32' from the evaporator 20 during the final rinse phase KP, it cools down again, here in the exemplary embodiment to a temperature of approximately 2 °C at the end of the final rinse phase KP at time tKA. After the rinsing liquid has been pumped out of the rinsing tank 2 as completely as possible at the end of the final rinse phase KP or the heat pump 14 has been switched off at time tKA, the drying phase TP follows at time tTE = tKA. This ends - here in the exemplary embodiment, for example, after approximately 1 h (hour) - at time tTA. In this example, the wall temperature WT only rises slowly from about 2 °C to about 17 °C.This flat curve of the wall temperature WT is in the . Fig. 4 is shown in dash-dotted lines and designated TW0. Since the wall temperature WT of the areas of the building wall 27 which are flowed through by the preceding heat pump operation with cold air 32' during the drying phase TP from the beginning of the drying phase at tTE is for a long time or mostly below or close to the dew point temperature - here, for example, about 14 °C, these cold areas or zones of the building wall 27 can become damp and the risk of mold growth increases there. In the embodiment of Fig. 4, the building wall 27 heats up after about 0.5 h, ie after half an hour, from the switch-off time tKA of the heat pump 14, first to a wall temperature of about 14° C, and after 1 h only to 17° C. In order to avoid a risk of moisture and / or mold on the building wall, after the end of the final rinse phase KP and after waiting for a dripping phase such as P1, here in the exemplary embodiment of about 3 to 5 minutes, in which condensate can drip off the evaporator 20, the air conveying device 26 is switched on and operated from the time such as tLE1 > tKA for a follow-up phase such as NP1 of the time duration NZ1 - here preferably until the end of the drying phase TP. Since air is sucked in with the help of the air conveying device 26, which on its suction path passes through one or more components that emit waste heat, such asthe compressor 16 is preheated in a favorable manner to a temperature higher than the ambient temperature RT, and this preheated air 32'' is blown onto the building wall 27 without major heat loss after flowing through the structure of the deactivated evaporator 20 (compressor 16 is switched off), the temperature on its air-flown surface can be brought much earlier and faster (than in the case without a run-on phase of the air conveying device 26) to a level that is higher than the dew point temperature in the gap space 28. Here in the embodiment of . Fig. 4, this increase in wall temperature WT is illustrated by a solid curve TW1, which is significantly steeper than the curve TW0 resulting from the case without the overrun operation of the air conveying device 26. While the wall temperature in the case without the overrun phase (dash-dotted curve TW0) only reaches the dew point temperature of approximately 14 °C after 0.5 h (hours), this is reached much earlier with the overrun phase NP1 - here at approximately 0.15 h (hours) - and then exceeded. The wall temperature WT rises by the end of the overrun phase NP1, corresponding to TW1, to 24 °C, with a significant safety margin above the dew point temperature, so that the surface of the building wall 27 can be reliably dried and / or kept dry. In the Fig. 4, a second follow-up phase NP2 of the air conveying device 26 is additionally shown, which begins at a greater time interval P2 (> P1), here in the exemplary embodiment, for example, of approximately 20 min (minutes), at the time tLE2 > tLE1 and lasts for a time period NZ2 < NZ1 until the end of the drying phase TP. Here, too, the wall temperature WT rises earlier and faster (compared to the curve TWO of the wall temperature WT in the case without a follow-up phase of the air conveying device 26) according to the curve TW2 at the surface of the building wall 27, which is supplied with the preheated air 32'' by means of the air conveying device 26, to a temperature level above the dew point temperature of approximately 14°C here, and reaches approximately 24°C at the end of the follow-up phase NP2 in the exemplary embodiment.

[0099] In general terms, at least one air conveying device, in particular the one assigned to the evaporator for heat pump operation (several air conveying devices next to or above one another are also possible), can be automatically switched on for follow-up operation, preferably at a time interval after the end of the last heating phase carried out by the heat pump for rinsing liquid that can be applied to dishes, glasses or similar wash items for cleaning them. The last heating phase for rinsing liquid carried out by the heat pump takes place in particular during the final rinse phase of the respective dishwashing program to be carried out, during which final rinse liquid, i.e. water mixed with rinse aid, is circulated by means of a circulating pump in the circulation circuit of the household dishwasher and applied to the wash items in the wash tub.The final rinse phase is preferably the last partial rinse phase of the respective dishwashing program, during which the dishes are rinsed with dishwashing liquid. The final heating phase for dishwashing liquid, carried out by the heat pump, preferably begins with the start of the final rinse phase and preferably ends with the end of the final rinse phase of the dishwashing program and thus with the end of the actual rinse cycle caused by this, during which the dishes to be cleaned are exposed to dishwashing liquid and become wet. This is followed in particular by a drying cycle to dry the dishes during the final drying phase of the dishwashing program. In addition, the drying phase can also be followed by a storage phase, during which the previously rinsed and then dried dishes remain in the wash tub.

[0100] The post-run operation or ventilation operation is preferably carried out outside of the actual wash cycle. In particular, the post-run operation takes place during the drying phase of the dishwashing program, during which the previously wet washed dishes are dried in the wash tub, and / or in a storage phase following the drying phase (so-called "storage function phase"), during which the rinsed and dried dishes are stored in the wash tub. However, it is also possible that the dishes have already been emptied from the wash tub during the post-run operation. In the post-run operation, air such as 32, in particular air preheated by waste heat from the household dishwasher such as 32", is pumped onto the building wall and / or kitchen unit wall that has previously been cooled during heat pump operation and that is located behind and / or next to the household dishwasher.

[0101] This run-on operation is possible and sensible without operating the heat pump, as this reduces or at least virtually eliminates the risk of air, which is conveyed through the wall, in particular the rear wall, of the appliance body of the household dishwasher to the building wall and / or kitchen furniture wall by means of the air conveying device used for run-on operation, being cooled at the evaporator or loaded with liquid or moisture.

[0102] If the air conveying device can be switched on at least 3 minutes, in particular 3 to 5 minutes, after the end of the actual rinsing cycle of the respective dishwashing program, a large part of the water condensed on the evaporator has already dripped downwards, in particular into a condensate tray or similar located below the evaporator.

[0103] If necessary, ie under certain practical circumstances, it may be advisable to equip the air conveyor with a dripping phase (see e.g. P1 in the Fig. 4) greater time interval (see e.g. P2 in the Fig. 4) - for example, with a time interval of at least 20 minutes - after the end of the last heating phase for rinsing liquid carried out by the heat pump, in particular the final rinse phase. This can then give the heat pump itself, in particular, sufficient time to allow the evaporator to warm up sufficiently in addition to the dripping of condensate. This reduces, or at least almost completely prevents, the risk of the air conveyed to the building wall and / or kitchen unit wall by the air conveying device used for the follow-up operation being cooled and / or loaded with liquid or moisture as it flows through the evaporator structure.

[0104] In particular, the time interval between this final shutdown of the heat pump 14, i.e., the time tKA from which the temperature of the parts of the heat pump 14, in particular of the evaporator 20, slowly adjusts to the temperature of the ambient air 32 present outside the household dishwasher, can be at least 40 minutes before the air conveying device 26 can be switched on for the after-run operation. This further reduces, or at least almost completely prevents, the risk that the air conveyed to the building wall and / or kitchen unit wall by the air conveying device used for the after-run operation will be cooled and / or loaded with liquid or moisture as it flows through the evaporator structure.From the time the heat pump is switched off until the air conveying device provided for the after-run operation is switched on, the drying and heating of the building wall and / or kitchen furniture wall and / or the evaporator of the heat pump can proceed largely unaffected by the waste heat from the household dishwasher.

[0105] The air conveying device 26, already outlined in its function for the run-on operation, does not have to be provided as a separate structural unit, but can be assigned to the at least one evaporator 20 and thus fulfill its main function during operation of the heat pump 14. The air conveying device 26 is then suitable for conveying air 32 from the surrounding space through the structure of the evaporator 20 - here in the exemplary embodiment preferably into an area 28 diametrically opposite the front V of the dishwasher 1, behind the rear wall R and / or next to one or two side walls S of the dishwasher 1. Fig. 3 only the conveyance of the air 32 behind the rear wall R of the dishwasher 1 is shown.

[0106] For this purpose, the air conveying device 26 can, in particular, comprise a conveying wheel 30 that is rotatable about an axis that is horizontal or at least nearly horizontal in the operating position of the household dishwasher 1, which draws in the ambient air 32 through slots or openings in the appliance body 5, in particular through the ventilation slots 31 on the front V, and directs it rearward through the rear wall R toward the building wall 27. Other air conveying devices 26 are, of course, also possible.

[0107] Using the described air path, the air conveying device 26 can convey relatively warm and dry air 32 from the ambient air against a building wall 27 located behind the dishwasher 1 in the operating position, thus displacing the moist and cold air that is present after the heat pump has been activated. This very effectively counteracts the risk of mold and mildew.

[0108] Particularly sustainable heating of the building wall 27 and the area 28 in front of the building wall 27 can be achieved if the air conveying device 26 is switched on for more than 30 minutes in follow-up operation. But even if this is interrupted, for example, because a new rinse cycle is about to begin, the effect on mold prevention is significant.

[0109] In particular, the switched-on operating time of the air conveying device 26 in the described overrun operation is more than 45 minutes.

[0110] For maximum energy efficiency, the switched-on operating time of the air conveying device 26 in overrun mode is a maximum of 90 minutes without interruption, since no further heating by the ambient air 32 is to be expected after this time.

[0111] Energy efficiency is also improved if the conveying capacity of the air conveying device 26 in the run-on mode is reduced compared to the conveying capacity of the air conveying device 26 when the heat pump 14 is switched on.

[0112] Different models are possible for the switch-on time and / or the duration of the run-on operation: In the simplest variant, the time interval after tKA until the air conveying device 26 is switched on can be preset.

[0113] A further possibility provides that the time interval until the air conveying device 26 is switched on for the after-run operation and / or the duration of the after-run operation depends on the ambient temperature in the room. This temperature can, for example, be detected by an already present temperature sensor on the heating pump (not shown here) integrated into the circulation circuit of the household dishwasher before or during the wash cycle. The corresponding time is then selected as the interval to tKA, whereby the following rule of thumb applies in particular: the higher the temperature of the ambient air 32, the shorter the time interval until the after-run operation is switched on and / or the shorter the duration of the after-run operation can be.

[0114] A third possibility provides that the time interval until the air conveying device 26 is switched on for the after-run operation and / or the duration of the after-run operation depends on a temperature measured at the evaporator 20 and / or in the vicinity of it in the area of ​​the rear wall R. This temperature can preferably be recorded in a time-synchronized manner so that its profile can be determined. It can therefore serve well as an input parameter for controlling the after-run operation, in which in particular a suitable switch-off time for the after-run operation can be determined based on a sufficiently high measured temperature. In addition to or independently of a temperature sensor, a sensor for the air humidity in the area of ​​the evaporator 20 and / or rear wall R can also be provided. This sensor could also protrude into the space 28 between the rear wall R or side wall S and the building wall 27.

[0115] It may be expedient to align the time interval until the air conveying device 26 is switched on for the run-on operation in such a way that the building wall 27 is warmed up to a temperature above the dew point for water. Otherwise, a negative effect could result from the supply of initially relatively humid air to the building wall 27, which should be avoided at all costs. This air would otherwise impact the building wall 27 and promote mold growth there rather than helping to prevent it. Relatively humid air could arise in particular if the air conveying device 26 conveys ambient air 32 through the structure of the evaporator 20 when the evaporator is still too wet and / or frosty after the heat pump 14 has been switched off.

[0116] For this temperature increase of the building wall 27 located to the side and / or behind the rear wall R, no additional heating is required, but in the time after the wash cycle, in particular the final rinse cycle KP, until the air conveying device 26 for the after-run operation is switched on, a building wall 27 located behind and / or next to the dishwasher 1 can be heated by waste heat from the dishwasher 1. This temperature increase is in the right area (right of the time tKA) in Fig. 4 recognizable.

[0117] The dishwasher 1 described is operated in such a way that after the heat pump 14 is switched off at time tKA, the air conveying device 26 is switched on for a follow-up operation at a time interval therefrom and at a time interval from the end of a wash cycle for cleaning dishes, glasses or similar wash items in an automated manner, i.e. without any necessary user action.

[0118] The air conveying device 26 is therefore switched on and operated at least during the post-run operation outside of the rinse cycle and without operation of the heat pump 14. This process can be automatically aborted before the start of the post-run operation or even during the post-run operation if the user starts a new rinse cycle.

[0119] In Fig. 4, the temperature curves TW1, TW2 when using the overrun mode clearly show that the overrun mode significantly increases the final temperature reached on the building wall 27 behind the dishwasher 1 and also accelerates the temperature rise behind the dishwasher after the heat pump 14 has stopped using. The overrun mode therefore has two positive effects for protecting the environment behind and / or next to the dishwasher 1.

[0120] As described above, the air conveying device 26 switches on for the after-run operation at a time interval of at least 3 minutes after the end of the wash cycle, wherein the switch-on time can be fixed or can be dependent on a measured temperature of the ambient air in the room and / or can be dependent on one or, in particular, several temperatures measured in the vicinity of the building wall 27 after the end of the wash cycle. In the latter case, true control of the after-run operation can result. In all cases, a program for switching on and the after-run operation can be implemented in a control unit CO of the heat pump 14 or in a control unit SCO of the household dishwasher 1 in terms of hardware and / or, in particular, software.

[0121] In a variation of the above case, according to which a dripping phase such as P1 or P2 lies between the end of the final rinse phase KP or the last heating process for rinsing liquid carried out by the heat pump 14 and the start of the after-run operation or ventilation operation such as NP1 or NP2 carried out by the air conveying device 26, it may even be possible for the air conveying device 26 to simply continue running, i.e. to continue its operation, for a follow-up time such as until the end of the drying phase TP after the end of the final rinse phase KP or after the end time of the last heating process for rinsing liquid carried out by the heat pump 14, from which time the compressor 16 is switched off. The waiting time, in particular the dripping time, such as P1 or P2, is then omitted.Any ingress of moisture from parts of the evaporator 20 that are still moist and / or frosted at the start of the after-run operation into the air flowing thereto may nevertheless be uncritical during the subsequent ventilation of the building wall 27 by this air, in particular if the condensate drips off the evaporator quickly or in a short time and / or the temperature of the blown-out, preheated air 32" is sufficient, ie far enough above the dew point temperature in the area of ​​and / or on the building wall 27.

[0122] As already explained above, the heat pump 14 can be pre-assembled, filled with working fluid 17, and tested for leaks before installation in the dishwasher. The heat pump 14, at least with its essential components 16, 18, 19, 20, 21 and the air conveying device 26, can be mechanically fixed to a supporting unit 15, forming a modular unit. Any temperature and / or humidity sensors can also be part of this module and can therefore be pre-assembled for their function during run-on operation before installation in the dishwasher 1, particularly in the base 12, which is very spatially limited and therefore problematic for installation. Their function – including run-on operation – can be tested under various conditions, for example, under different ambient temperatures.

[0123] If necessary, the air conveying device for the run-on phase or ventilation phase can also be formed by at least one existing air conveying device, which is provided in and / or on the household dishwasher 1 for a different function than the air conveying device 26, which is assigned to the evaporator 20 for flowing and / or passing ambient air during the respective washing liquid heating phase to be carried out by means of heat pump operation. Such a second, already existing air conveying device is preferably not arranged in front of the evaporator 20, but at a different location on the household dishwasher 1. In the Fig.2, a second air conveying device is shown, by way of example, only schematically and in dash-dotted lines on the rear wall R of the household dishwasher and is designated 26'. It ensures ventilation of the gap space 28 during the run-on phase or ventilation phase, alone or, if appropriate, in combination with the air conveying device 26 arranged in front of the evaporator 20. In particular, with its aid, ambient air, which is and / or is preheated by one or more waste heat-emitting components of the household dishwasher, can be conveyed, in particular blown, into the gap space 28 and / or onto the one or more cold zones or areas of the building wall 27 during the ventilation phase.

[0124] According to a further alternative, however, at least one air conveying device provided specifically or separately for ventilation operation, such as 26'', may also be expedient in addition to the air conveying device 26 provided for heat pump operation upstream of the evaporator 20, in particular at a different location than this. It ensures ventilation of the gap space 28 during the after-run phase or ventilation phase, alone or possibly also in combination with the air conveying device 26 arranged upstream of the evaporator 20. In particular, it makes it possible, during the ventilation phase, to convey, in particular to blow, ambient air that is and / or is being preheated by one or more components of the household dishwasher that emit waste heat into the gap space 28 and / or onto the one or more cold zones or areas of the building wall 27.

Claims

[1] Dishwasher (1), in particular a household dishwasher, with at least one heat pump (14) comprising at least one compressor (16), a condenser (18), an expansion element (19) and an evaporator (20), which are connected to one another via line regions (21) for conveying a working medium (17) which changes its state of aggregation during operation, wherein the heat pump (14) is assigned at least one supply line (22) and one discharge line (23) of washing liquid (24) which can be circulated in the dishwasher (1), and wherein at least one air conveying device (26) is provided, characterized bythat the air conveying device (26) is operable for a follow-up time (NZ1, NZ2) after the end (tKA) of the last heating phase (AHK) for rinsing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the final rinsing phase (KP), of at least one dishwashing program (GP) to be carried out, during which, in one or more partial rinsing phases (RP, KP), the rinsing liquid (24) respectively used for cleaning dishes, glasses or similar items can be heated in at least one heating phase (AHR, AHK) by means of the heat pump (14). [2] Dishwasher (1) according to claim 1, characterized bythat the air conveying device (26) is assigned to the evaporator (20) of the heat pump (14), and that this air conveying device (26) continues to run for a follow-up time (NZ1, NZ2), in particular during the drying phase (TP) of the respective dishwashing program (GP), after the end (tKA) of the last heating phase (AHK) for washing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the final rinsing phase (KP) of the respective dishwashing program (GP) to be carried out. [3] Dishwasher (1) according to claim 1, characterized bythat the air conveying device (26) is assigned to the evaporator (20) of the heat pump (14), and that this air conveying device (26) can be switched on automatically after the end (tKA) of the last heating phase (AHK) for washing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the final rinse phase (KP), of the respective dishwashing program (GP) to be carried out, with a time interval (P1, P2) from this end (tKA), in particular in the drying phase (TP) of the dishwashing program (GP), and can be operated for a follow-up time period (NZ1, NZ2), in particular until the end (tTA) of the drying phase (TP) of the dishwashing program (GP). [4] Dishwasher (1) according to claim 3, characterized bythat the air conveying device (26) can be switched on with a time interval (P1) of at least 3 minutes after the end of the last heating phase (AHK) for washing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the final rinsing phase (KP) of the respective dishwashing program (GP) to be carried out. [5] Dishwasher (1) according to at least one of claims 1 to 4, characterized by that the air conveying device (26) is assigned to the evaporator (20) and is suitable for conveying air (32) from the environment at the installation location of the dishwasher (1) through the structure of the evaporator (20) and out of the dishwasher, in particular into an area (28) diametrically opposite the front side (V) of the dishwasher (1) behind and / or into an area next to the dishwasher (1). [6] Dishwasher (1) according to at least one of claims 1 to 5, characterized byin that the air conveying device (26) comprises a conveying wheel (30) which can be rotated about an axis which is horizontal or at least almost horizontal in the operating position of the dishwasher (1). [7] Dishwasher (1) according to at least one of claims 1 to 6, characterized by that the air conveying device (26) is suitable for conveying air (32) against a building wall (27) and / or kitchen furniture wall located behind and / or next to the dishwasher (1) in the operating position of the dishwasher. [8] Dishwasher (1) according to at least one of claims 1 to 7, characterized by that the switched-on operating time or follow-up time (NZ1, NZ2) of the air conveying device (26) in follow-up operation is at least 10 minutes, in particular between 20 minutes and 60 minutes. [9] Dishwasher (1) according to at least one of claims 1 to 8, characterized bythat the after-run operation of the air conveying device (26) lasts at most until the end of the drying phase (TP) of the respective dishwashing program (GP) to be carried out. [10] Dishwasher (1) according to at least one of claims 1 to 9, characterized by that the conveying capacity of the air conveying device (26) in the follow-up operation can be reduced compared to the conveying capacity of the air conveying device (26) when the heat pump (14) is switched on. [11] Dishwasher (1) according to at least one of claims 1 to 10, characterized by that the run-on time (NZ1, NZ2) and / or the time interval (P1, P2) until the air conveying device (26) is switched on for the run-on operation depends on an ambient temperature at the installation location of the dishwasher (1). [12] Dishwasher (1) according to at least one of claims 1 to 11, characterized bythat the run-on time (NZ1, NZ2) of the air conveying device (26) and / or the time interval (P1, P2) until the air conveying device (26) is switched on for the run-on operation depends on a temperature measured at the evaporator (20) or in its immediate vicinity. [13] Dishwasher (1) according to at least one of claims 1 to 12, characterized byin that the run-on time (NZ1, NZ2) of the air conveying device (26) and / or the time interval (P1, P2) until the air conveying device (26) is switched on for the run-on operation is dimensioned such that a building wall (27) and / or kitchen furniture wall located behind and / or next to the dishwasher (1) can be or is heated up to a temperature above the dew point for water on its surface, which can be directly or indirectly flowed over by the air (32) flowing through the structure of the evaporator (20) after said air has flowed out of the dishwasher (1), in particular which is at the level of the evaporator (20) in the area closest to it. [14] Dishwasher (1) according to one of claims 3 to 13, characterized bythat in the time (P1, P2) after the end (tKA) of the last heating phase (AHK) for rinsing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the final rinse phase (KP) of the respective dishwashing program (GP) to be carried out, until the air conveying device (26) for the follow-up operation is switched on, a building wall (27) and / or kitchen furniture wall located behind and / or next to the dishwasher (1) can be heated by waste heat from the dishwasher (1). [15] Method for operating a dishwasher (1) with at least one heat pump (14) comprising at least one compressor (16), a condenser (18), an expansion element (19) and an evaporator (20), which are connected to one another via line regions (21) for conveying a working medium (17) which changes its state of aggregation during operation, wherein the heat pump (14) is assigned at least one supply line (22) and one discharge line (23) of washing liquid (24) which can be circulated in the dishwasher (1), and wherein at least one air conveying device (26) is provided, in particular according to at least one of the preceding claims, characterized bythat the air conveying device (26) is operated for a follow-up time (NZ1, NZ2) after the end (tKA) of the last heating phase (AHK) for rinsing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the final rinsing phase (KP), of at least one dishwashing program (GP) to be carried out, during which, in one or more partial rinsing phases (RP, KP), the rinsing liquid (24) respectively used for cleaning dishes, glasses or similar items to be washed is heated in at least one heating phase (AHR, AHK) by means of the heat pump (14). [16] Method according to claim 15, characterized bythat the air conveying device (26) is assigned to the evaporator (20) of the heat pump (14), and that this air conveying device (26) continues to run for a follow-up time (NZ1, NZ2), in particular during the drying phase (TP) of the respective dishwashing program (GP), after the end (tKA) of the last heating phase (AHK) for washing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the final rinsing phase (KP) of the respective dishwashing program (GP) to be carried out. [17] Method) according to claim 15, characterized bythat the air conveying device (26) is assigned to the evaporator (20) of the heat pump (14), and that this air conveying device (26) is automatically switched on after the end (tKA) of the last heating phase (AHK) for washing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the final rinse phase (KP), of the respective dishwashing program (GP) to be carried out, with a time interval (P1, P2) from this end (tKA), in particular in the drying phase (TP) of the dishwashing program (GP), and is operated for a follow-up time period (NZ1, NZ2), in particular until the end (tTA) of the drying phase (TP) of the dishwashing program (GP). [18] Method according to claim 17, characterized bythat the air conveying device (26) is switched on with a time interval (P1) of at least 3 minutes after the end (tKA) of the last heating phase (AHK) for washing liquid (24) carried out by means of the heat pump (14), in particular after the end (tKA) of the final rinsing phase (KP) of the respective dishwashing program (GP) to be carried out. [19] Method according to at least one of claims 15 to 18, characterized by that the run-on time (NZ1, NZ2) of the air conveying device (26) and / or the time interval (P1, P2) until the air conveying device (26) is switched on is dependent on a measured temperature of the ambient air at the installation location of the dishwasher (1). [20] Method according to one of claims 15 to 19, characterized bythat the run-on time (NZ1, NZ2) of the air conveying device (26) and / or the time interval (P1, P2) until the air conveying device (26) is switched on is dependent on a temperature measured after the end of the rinsing phase (SP) in the vicinity of a building wall (27) and / or kitchen furniture wall, which borders on the air outlet opening (LA) of the dishwasher (1), from which the air (32) flowing through the structure of the evaporator (20) flows out. [21] Method according to one of claims 15 to 20, characterized bythat the run-on time (NZ1, NZ2) of the air conveying device (26) and / or the time interval (P1, P2) until the air conveying device (26) is switched on for the run-on operation is set in such a way that a building wall (27) and / or kitchen furniture wall located behind and / or next to the dishwasher (1) is heated to a temperature above the dew point for water on its surface, which is directly or indirectly flowed over by the air (32) flowing through the structure of the evaporator (20) after flowing out of the dishwasher (1), in particular which is at the level of the evaporator (20) in the area closest to it.

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