Method and device for carrying out a hygiene program and heat pump dryer

Abstract

A method for performing a hygiene program of a heat pump dryer (100), wherein the heat pump dryer (100) comprises a drum (102) for receiving laundry, a heat pump (108) for drying and tempering the process air, an auxiliary heating device (112) for heating the process air, a process air blower (110) for conveying the process air in a cycle through the drum (102), the heat pump (108) and the auxiliary heating device (112) back into the drum (102), a process air temperature sensor (134) for detecting a process air temperature of the process air on the outlet side of the drum (102) and a refrigerant temperature sensor (130) for detecting a refrigerant temperature of a refrigerant of the heat pump (108) on the outlet side of a compressor (122) of the heat pump (108), comprises a step of driving the process air blower (110) to convey the process air in the circuit,a step of controlling the compressor (122) of the heat pump (108) to set the refrigerant temperature to a reduced setpoint for the hygiene program, which is lower than a maximum setpoint for a drying program of the heat pump dryer (100), a step of operating the auxiliary heating device (112) to set the process air temperature to a preset value for the hygiene program, and a step of terminating the hygiene program after a predefined holding time has elapsed.

Description

[0001] The invention relates to a method and a device for carrying out a hygiene program of a heat pump dryer and to a heat pump dryer.

[0002] Hygienic programs are known to exist in tumble dryers. A hygiene program can, for example, be a certified program (drying level) designed for sanitizing wet laundry. This sanitization is achieved primarily through sufficiently high temperatures and holding times. Such hygiene programs can therefore have relatively long cycle times. Furthermore, the hygiene program may only be suitable for damp laundry, as the holding time is typically controlled by a residual moisture signal.

[0003] DE 10 2021 106 619 A1 relates to a method for carrying out a hygiene program for a laundry treatment device for damp laundry, whereby holding time is controlled via residual moisture.

[0004] The approach presented here aims to create an improved method and device for carrying out a hygiene program of a heat pump dryer and an improved heat pump dryer.

[0005] According to the invention, this problem is solved by a method and a device for carrying out a hygiene program of a heat pump dryer and by a heat pump dryer with the features of the main claims. Advantageous embodiments and further developments of the invention are described in the following dependent claims.

[0006] The advantages achievable with the invention consist of a reduced cycle time compared to conventional hygiene programs. Furthermore, it allows for the treatment of dry laundry within the hygiene program. This not only results in faster program cycles but also reduces mechanical stress on the textiles and thermal stress on the dryer, particularly on the dryer's electrical components, thus protecting both the laundry and the appliance. Advantageously, it also enables the processing of both dry and wet laundry in the same program.

[0007] A method for performing a hygiene program of a heat pump dryer, wherein the heat pump dryer comprises a drum for holding laundry, a heat pump for drying and tempering the process air, an auxiliary heating device for heating the process air, a process air blower for circulating the process air through the drum, the heat pump and the auxiliary heating device back into the drum, a process air temperature sensor for detecting the process air temperature at the outlet of the drum, and a refrigerant temperature sensor for detecting the refrigerant temperature at the outlet of a compressor of the heat pump, comprises the following steps: Driving the process air blower to circulate the process air in the loop; controlling the heat pump compressor to set the refrigerant temperature to a reduced setpoint for the hygiene program, which is lower than a maximum setpoint for a drying program of the heat pump dryer; operating the auxiliary heating device to set the process air temperature to a preset value for the hygiene program; and ending the hygiene program after a predefined holding time has elapsed.

[0008] The heat pump dryer can be used to dry laundry. Laundry to be dried can be placed in the drum. The laundry can be dried using process air. The process air can be dried and tempered using the heat pump and then fed into the drum. A process air blower can be used to circulate the process air. The heat pump, as with other known heat pumps, can comprise a refrigerant circuit with an evaporator, a compressor, a condenser, and an expansion valve. "Setting" can refer specifically to regulating the system. The refrigerant temperature can represent the temperature of the refrigerant in a section of the refrigerant circuit located between the compressor and the condenser. The refrigerant temperature can be represented by a refrigerant temperature value.The refrigerant temperature can be measured and provided using the refrigerant temperature sensor. The process air temperature can represent the temperature of the process air in a section of a duct located between the condenser and an inlet to the drum. The process air temperature can be represented by a process air temperature value. This value can be measured and provided using the process air temperature sensor.

[0009] In the context of temperature values, "represent" can mean that the corresponding temperature, or an order of magnitude of the corresponding temperature, is displayed or represented by the corresponding temperature value. Thus, the respective temperature value can also correspond to the respective temperature. The "drive" step can be executed using a blower control signal to control the speed of the process air blower. The "control" step can be executed using a compressor control signal to control the speed of the compressor. The "operate" step can be executed using a heating control signal to control the heating power of the auxiliary heating device. In the "terminate" step, the execution of at least the "control" and "operate" steps can be aborted. The hold time can begin running once the preset value is reached.The method can also include a step of measuring the process air temperature at the drum outlet using the process air temperature sensor. Furthermore, the method can include a step of measuring the refrigerant temperature at the heat pump compressor outlet using the refrigerant temperature sensor.

[0010] According to one embodiment, the compressor can be activated during the activation step to set the refrigerant temperature to a reduced setpoint of 90 degrees Celsius. Additionally or alternatively, the compressor can be activated during the activation step to set the refrigerant temperature to a reduced setpoint of at least 4 degrees Celsius below the maximum setpoint. This embodiment offers the advantage that the high pressure in the refrigerant circuit can be reduced during the hygiene program. This reduces the stress on components of the heat pump dryer.

[0011] The activation step can also be executed when a drying program of the heat pump dryer, preceding the hygiene program, reaches a predefined process phase. This predefined process phase can be the end of the drying program or a process phase immediately preceding the end of the drying program. This configuration offers the advantage that the temperature in the refrigerant circuit, and thus the thermal load on the heat pump dryer's components, can be reduced early on if the hygiene program is to be executed after the drying program.

[0012] Furthermore, the activation step can be executed if, during a drying program of the heat pump dryer preceding the hygiene program, the residual moisture content of the process air at the drum outlet falls below a predefined threshold. This residual moisture content can be represented by a residual moisture value, which can be detected and provided by a residual moisture sensor. This design offers the advantage that the temperature in the refrigerant circuit, and thus the thermal load on the heat pump dryer's components, can be reduced in a timely manner if the hygiene program is to be executed immediately following the drying program.

[0013] According to one embodiment, during the operating step, the auxiliary heating device can be operated to adjust the process air temperature to a preset value between 60 and 70 degrees Celsius, between 62.5 and 67.5 degrees Celsius, or 65 degrees Celsius. Such an embodiment offers the advantage of enabling effective hygienic processing of both wet and dry laundry.

[0014] Furthermore, in the final step, the hygiene program can be terminated after a holding time of between 2500 and 3500 seconds, between 2750 and 3250 seconds, or 3000 seconds. This design offers the advantage of reliably ensuring hygienic processing of laundry, while also preventing unnecessarily long cycle times at low ambient temperatures compared to conventional residual moisture control or temperature control alone.

[0015] According to one embodiment, in which the heat pump dryer has an additional process air temperature sensor for detecting a further process air temperature at the drum inlet, the auxiliary heating device can be operated during the operating phase to set the temperature difference between this additional process air temperature and the main process air temperature to a maximum of 5 Kelvin. This additional process air temperature can be represented by a further process air temperature value, which can be detected and provided by the additional process air temperature sensor. Such an embodiment offers the advantage that even more reliable and precise process control can be achieved by monitoring the process air at the drum inlet and outlet.

[0016] The approach presented here further creates a device designed to perform, control, and implement the steps of a variant of the method presented here in appropriate facilities. This embodiment of the invention in the form of a device also allows the problem underlying the invention to be solved quickly and efficiently.

[0017] The device can be configured to read input signals and, using these input signals, determine and provide output signals. An input signal can, for example, be a sensor signal readable via an input interface of the device. An output signal can be a control signal or a data signal that can be provided at an output interface of the device. The device can be configured to determine the output signals using a processing instruction implemented in hardware or software. For example, the device can include a logic circuit, an integrated circuit, or a software module and can be implemented, for example, as a discrete component or comprised of a discrete component. The device can be designed as a control unit, or features of the device can be implemented by a corresponding control unit.

[0018] A heat pump dryer includes the following features: a drum for holding laundry; a heat pump for drying and tempering the process air; an auxiliary heating device for heating the process air; a process air blower for circulating the process air through the drum, the heat pump, and the auxiliary heating device back into the drum; a process air temperature sensor for detecting the process air temperature at the drum outlet; a refrigerant temperature sensor for detecting the refrigerant temperature at the heat pump compressor outlet; and an embodiment of a device mentioned herein, wherein the device is connected to the heat pump compressor, the auxiliary heating device, the process air blower, the process air temperature sensor, and the refrigerant temperature sensor in a signal-transmitting manner.

[0019] Advantageously, the approach described here can be implemented in conjunction with known heat pump dryers.

[0020] A computer program product or computer program with program code that can be stored on a machine-readable medium such as semiconductor memory, hard disk memory, or optical memory is also advantageous. If the program product or program is executed on a computer or control unit, it can be used to carry out, implement, and / or control the steps of the method according to one of the embodiments described herein.

[0021] Although the described approach is based on a household appliance, the approach described here can be used accordingly in connection with a commercial or professional device, for example a medical device, such as a cleaning or disinfection device, a small sterilizer, a large-capacity disinfector or a container washing system.

[0022] An embodiment of the invention is shown purely schematically in the drawings and is described in more detail below. It shows Figure 1 is a schematic representation of an embodiment of a heat pump dryer; Figure 2 is a schematic representation of an embodiment of a heat pump dryer; Figure 3 is a flowchart of an embodiment of a method for carrying out a hygiene program of a heat pump dryer; Figure 4 is a graphical representation of temperature and humidity profiles for wet laundry in connection with an embodiment of a heat pump dryer; and Figure 5 is a graphical representation of temperature and humidity profiles for dry laundry in connection with an embodiment of a heat pump dryer.

[0023] Figure 1Figure 1 shows a schematic representation of an embodiment of a heat pump dryer 100, which is also referred to as a dryer or clothes dryer. Similar to known heat pump dryers, the heat pump dryer 100 comprises a rotatable drum 102 into which laundry can be placed. The drum 102 can be closed by a door. During operation of the heat pump dryer 100, the laundry in the drum 102 is dried using process air or a process air stream 104. The process air stream 104 is guided through the drum 102 and a channel 106. The channel 106 has an inlet leading out of the drum 102 and an outlet leading into the drum 102.

[0024] Within the channel 106, a heat pump 108 for drying and tempering the process air of the process air stream 104, a process air blower 110 for conveying the process air, and an auxiliary heating device 112 are arranged. The heat pump 108 has a refrigerant circuit with an evaporator 120, a compressor 122, a condenser 124, and an expansion valve. The process air blower 110 is designed to convey the process air in a closed loop through the drum 102, the heat pump 108, and the auxiliary heating device 112, or along the drum 102 and back into the drum 102. The auxiliary heating device 112 is arranged between the heat pump 108 and the outlet of the channel 106. The auxiliary heating device 112 is designed to heat the process air.

[0025] Furthermore, the heat pump dryer 100 comprises a refrigerant temperature sensor 130, a process air temperature sensor 134, an optional additional process air temperature sensor 132, and an optional residual moisture sensor 136. The refrigerant temperature sensor 130 is located in the refrigerant circuit between the compressor 122 and the condenser 124. The refrigerant temperature sensor 130 is designed to detect the refrigerant temperature of the heat pump 108 at the outlet of the compressor 122. The process air temperature sensor 134 is located in the duct 106 for guiding the process air flow 104 between the drum 102 and the heat pump 108. The process air temperature sensor 134 is designed to detect the process air temperature at the outlet of the drum 102.

[0026] The optional additional process air temperature sensor 132 is arranged in the duct 106 for guiding the process air flow 104 between the process air blower 110 and the drum 102, more precisely in the area of ​​the auxiliary heating device 112 or between the auxiliary heating device 112 and the drum 102. The additional process air temperature sensor 132 is designed to detect an additional process air temperature at the inlet side of the drum 102. The optional residual moisture sensor 136 is arranged in the duct 106 for guiding the process air flow 104 between the drum 102 and the heat pump 108. The residual moisture sensor 136 is designed to detect residual moisture in the process air at the outlet side of the drum 102.

[0027] According to one embodiment, the auxiliary heating device 112 is designed as a QPD heater, the additional process air temperature sensor 132 as an NTC sensor after the QPD heater (additional process air temperature) and the refrigerant temperature sensor 130 as an NTC sensor after the compressor 122 (refrigerant temperature).

[0028] Furthermore, the heat pump dryer 100 has a device 150 configured to execute a hygiene program of the heat pump dryer 100. The device 150 is, for example, part of a control unit of the heat pump dryer 100. The device 150 is signal-transmitting and connected to the compressor 122 of the heat pump 108, the auxiliary heating device 112, the process air blower 110, the process air temperature sensor 134, and the refrigerant temperature sensor 130, and optionally also to the additional process air temperature sensor 132 and the residual moisture sensor 136. The device 150 is configured, among other things, to...Depending on the process air temperature of the process air on the outlet side of the drum 102, at least one control signal is to be provided to control the operation of at least one component of the heat pump dryer 100 involved in the hygiene program, for example a compressor control signal to control a speed of the compressor 122 and / or a blower control signal to control a speed of the process air blower 110 and / or a heating control signal to control a heating power of the auxiliary heating device 112.

[0029] The device 150 is configured to drive the process air blower 110 to circulate the process air in the circuit and to generate the process air flow 104. Furthermore, the device 150 is configured to control the compressor 122 of the heat pump 108 to set the refrigerant temperature to a reduced setpoint for the hygiene program, which is lower than the maximum setpoint for a drying program of the heat pump dryer 100. In addition, the device 150 is configured to operate the auxiliary heating device 112 to set the process air temperature to a preset value for the hygiene program. Finally, the device 150 is configured to terminate the hygiene program after a predefined holding period.

[0030] Figure 2 Figure 1 shows a schematic representation of an embodiment of a heat pump dryer 100. The heat pump dryer 100 is like the one described in Figure 1. Figure 1The described heat pump dryer was installed. Figure 2 The device and the residual moisture sensor are not shown for illustrative reasons, and the information regarding Figure 1 The throttle 226 mentioned is explicitly shown here.

[0031] According to one embodiment, the runtime of the hygiene program performed by the heat pump dryer 100, and in particular its device, is significantly reduced compared to conventional hygiene programs by using an electric auxiliary heater (QPD), i.e., the auxiliary heating device 112, by reducing the heating times. The thermal load on the compressor 122 and surrounding components is reduced by lowering the compressor control temperature or the refrigerant temperature when a certain drying stage is reached. This reduces the hot gas temperature and the high pressure in the refrigeration circuit or refrigerant circuit. The process or sequence of the hygiene program is controlled by the outlet temperature from the drum 102, i.e., by the process air temperature at the outlet of the drum 102. Therefore, the hygiene program can also be used for dry laundry. To avoid continuous operation, e.g.,To prevent damage at very low installation temperatures, a time monitoring system is also implemented.

[0032] According to one embodiment, the laundry temperature is regulated, for example 65 degrees Celsius, via the process air temperature (T_PL) after the drum 102, then a holding time of, for example, 3000 seconds for a sufficient hygienic effect (hygienization phase).

[0033] Furthermore, according to one embodiment, the compressor's control temperature (T_HGT), i.e., the refrigerant temperature, is reduced from, for example, 95 to 90 degrees Celsius to lower the high pressure during the hygienization phase or the hygiene program. The refrigerant temperature is lowered even before the hygienization phase or the hygiene program, particularly via a residual moisture signal.

[0034] Furthermore, according to one embodiment, the hygiene program implemented by the heat pump dryer 100 can be used for both wet and dry laundry by providing a time limit for the phases and a temperature limit, i.e., a process air temperature (T_PL) of, for example, 65 degrees Celsius. This also ensures the program runs reliably even at very cold installation temperatures.

[0035] According to one embodiment, a control system can be provided for an absolute value of the process air temperature (T_PL) of, for example, 65 degrees Celsius and for a temperature difference T_QPD - T_PL < 5K. Thus, the treatment chamber or drum 102 is monitored with regard to the temperature of the process air at the inlet and outlet of the treatment chamber or drum 102.

[0036] Figure 3Figure 3 shows a flowchart of an embodiment of method 350 for carrying out a hygiene program of a heat pump dryer. Method 350 can be carried out in conjunction with a heat pump dryer, as shown in Figure 350. Figure 1 and / or Figure 2 This is described, for example, using units or equipment of the heat pump dryer. The heat pump dryer device consists of... Figure 1 and / or Figure 2 The device is designed to perform the steps of the procedure 350 described herein. For this purpose, the device includes suitable units for performing the steps of the procedure 350 described herein.

[0037] Thus, method 350 can be carried out in conjunction with a heat pump dryer which has at least the following features: a drum for holding laundry, a heat pump for drying and tempering the process air, an auxiliary heating device for heating the process air, a process air blower for conveying the process air in a cycle through the drum, the heat pump and the auxiliary heating device back into the drum, a process air temperature sensor for detecting the process air temperature at the outlet of the drum, and a refrigerant temperature sensor for detecting the refrigerant temperature of the heat pump at the outlet of a heat pump compressor.

[0038] The procedure 350 comprises a drive step 352, a control step 354, an operation step 356, and a termination step 358. In drive step 352, the process air blower is driven to circulate the process air in the loop, for example, using a blower control signal to control the speed of the process air blower. In control step 354, the heat pump compressor is controlled to set the refrigerant temperature to a reduced setpoint for the hygiene program, which is lower than a maximum setpoint for a drying program of the heat pump dryer, for example, using a compressor control signal to control the speed of the compressor.In step 356 of the operation process, the auxiliary heating device is operated to set the process air temperature to a preset value for the hygiene program, for example, using a heating control signal to control the heating output of the auxiliary heating device. Subsequently, in step 358 of the termination process, the hygiene program is ended after a predefined holding period has elapsed.

[0039] The sequence of executing step 352 (driving), step 354 (controlling), and step 356 (operating) can be chosen as required and can also be carried out at least partially simultaneously.

[0040] According to one embodiment, in step 354 of the control process, the compressor is activated to set the refrigerant temperature to a reduced setpoint of 90 degrees Celsius and / or at least 4 degrees Celsius below the maximum setpoint. According to another embodiment, step 354 of the control process is executed when a drying program of the heat pump dryer preceding the hygiene program has reached a predefined process phase and / or when, during a drying program of the heat pump dryer preceding the hygiene program, the residual moisture content of the process air at the drum outlet falls below a predefined threshold.

[0041] According to one embodiment, in step 356 of the operation, the auxiliary heating device is operated to set the process air temperature to a preset value between 60 and 70 degrees Celsius, between 62.5 and 67.5 degrees Celsius, or 65 degrees Celsius. According to another embodiment, in which the heat pump dryer has an additional process air temperature sensor for detecting a further process air temperature at the drum inlet, the auxiliary heating device is operated in step 356 of the operation to set a temperature difference between the further process air temperature and the process air temperature to a maximum of 5 Kelvin.

[0042] According to one embodiment, in step 358 of the termination process, the hygiene program is terminated after a holding time of between 2500 and 3500 seconds, between 2750 and 3250 seconds, or 3000 seconds.

[0043] Figure 4Figure 1 shows a graphical representation of temperature and humidity profiles for wet laundry in conjunction with an exemplary embodiment of a heat pump dryer. The heat pump dryer corresponds to or is similar to the heat pump dryer shown in one of the figures described above.

[0044] The diagram shows time profiles for the refrigerant temperature 430, the process air temperature 432, the process air temperature 434, the residual moisture 436, the room humidity 462, and the room temperature 464. Furthermore, it shows a time profile of program phases 460 of programs implemented using the heat pump dryer, the maximum setpoint 430A and the reduced setpoint 430B of the refrigerant temperature 430, the target value 434X of the process air temperature 434, and the holding time t H.

[0045] From the presentation of Figure 4A reduction in the compressor's control temperature, i.e., the refrigerant temperature 430, from the maximum setpoint 430A, for example, 95 degrees Celsius, to the reduced setpoint 430B, for example, 90 degrees Celsius, is evident for the hygiene program. Furthermore, it is evident that the target value 434X for the process air temperature 434 is 65 degrees Celsius according to the embodiment shown here. It is also evident that the holding time t H is 3000 seconds. The hygiene program is performed for wet or damp laundry, preceded by a drying program.

[0046] Figure 5 Figure 1 shows a graphical representation of temperature and humidity profiles for dry laundry in conjunction with an exemplary embodiment of a heat pump dryer. The heat pump dryer corresponds to or is similar to the heat pump dryer shown in one of the figures described above.

[0047] The diagram shows time profiles for the refrigerant temperature 430, the process air temperature 432, the process air temperature 434, the room humidity 462, and the room temperature 464. Furthermore, it shows a time profile of program phases 460 of programs implemented using the heat pump dryer, the reduced setpoint 430B of the refrigerant temperature 430, the target value 434X of the process air temperature 434, and the holding time t H.

[0048] From the presentation of Figure 5The setting of the compressor's control temperature, i.e., the refrigerant temperature 430, to the reduced setpoint 430B, for example, 90 degrees Celsius, for the hygiene program is evident. Furthermore, it is evident that the target value 434X for the process air temperature 434 is 65 degrees Celsius according to the embodiment shown here. It is also apparent that the holding time t H is 3000 seconds. The hygiene program can therefore also be carried out for dry laundry in a time-controlled and temperature-controlled manner.

Claims

1. Method (350) for carrying out a hygiene program of a heat pump dryer (100), wherein the heat pump dryer (100) comprises a drum (102) for receiving laundry, a heat pump (108) for drying and tempering the process air, an auxiliary heating device (112) for heating the process air, a process air blower (110) for conveying the process air in a cycle through the drum (102), the heat pump (108) and the auxiliary heating device (112) back into the drum (102), a process air temperature sensor (134) for detecting a process air temperature (434) of the process air on the outlet side of the drum (102), and a refrigerant temperature sensor (130) for detecting a refrigerant temperature (430) of a refrigerant of the heat pump (108) on the outlet side of a compressor (122) of the heat pump. (108) wherein the method (350) comprises the following steps: driving (352) the process air blower (110) to convey the process air in the circuit;Controlling (354) the compressor (122) of the heat pump (108) to set the refrigerant temperature (430) to a reduced setpoint (430B) for the hygiene program, which is lower than a maximum setpoint (430A) for a drying program of the heat pump dryer (100); operating (356) the auxiliary heating device (112) to set the process air temperature (434) to a preset value (434X) for the hygiene program; and terminating (358) the hygiene program after a predefined holding time (t; H ).

2. Method (350) according to claim 1, wherein in step (354) of controlling the compressor (122) is controlled to adjust the refrigerant temperature (430) to a reduced setpoint (430B) of 90 degrees Celsius and / or at least 4 degrees Celsius below the maximum setpoint (430A).

3. Method (350) according to one of the preceding claims, wherein the step (354) of activation is performed when a drying program of the heat pump dryer (100) preceding the hygiene program reaches a predefined process phase (460).

4. Method (350) according to one of the preceding claims, wherein the step (354) of activation is performed when, during a drying program of the heat pump dryer (100) preceding the hygiene program, the residual moisture (436) of the process air on the outlet side of the drum (102) falls below a predefined threshold value.

5. Method (350) according to one of the preceding claims, wherein in step (356) of operation the auxiliary heating device (112) is operated to adjust the process air temperature (434) to a preset value (434X) between 60 and 70 degrees Celsius, between 62.5 and 67.5 degrees Celsius or 65 degrees Celsius.

6. Method (350) according to one of the preceding claims, wherein in step (358) of termination the hygiene program after a holding time (t H ) between 2500 and 3500 seconds, between 2750 and 3250 seconds, or is terminated by 3000 seconds.

7. Method (350) according to one of the preceding claims, wherein the heat pump dryer (100) has a further process air temperature sensor (132) for detecting a further process air temperature (432) of the process air on the inlet side of the drum (102), wherein in step (356) of operation the additional heating device (112) is operated to set a temperature difference between the further process air temperature (432) and the process air temperature (434) to a maximum of 5 Kelvin.

8. Device (150) configured to perform and / or control the steps of the method (350) according to any of the preceding claims in corresponding units.

9. Heat pump dryer (100) comprising the following features: a drum (102) for holding laundry; a heat pump (108) for drying and tempering the process air; an auxiliary heating device (112) for heating the process air; a process air blower (110) for circulating the process air through the drum (102), the heat pump (108) and the auxiliary heating device (112) back into the drum (102); a process air temperature sensor (134) for detecting a process air temperature (434) of the process air on the outlet side of the drum (102); a refrigerant temperature sensor (130) for detecting a refrigerant temperature (430) of a refrigerant of the heat pump (108) on the outlet side of a compressor (122) of the heat pump (108);and a device (150) according to claim 8, wherein the device (150) is connected to the compressor (122) of the heat pump (108), to the auxiliary heating device (112), to the process air blower (110), to the process air temperature sensor (134) and to the refrigerant temperature sensor (130) in a signal-transmitting manner.

10. Computer program product with program code for carrying out the method (350) according to any one of claims 1 to 7, when the computer program product is executed on a device (150) according to claim 8.

Images