Method of controlling a heating system component and heating system component

Abstract

The invention relates to a heating system component for a heating system for heating a fluid medium, comprising a carrier unit; and a heating unit coupled to the carrier unit; and a controller; wherein the carrier unit comprises a wet side and a dry side, the wet side corresponds to a surface of the carrier unit configured to be in contact with the fluid medium, and the dry side is located on a surface opposite to the wet side. A temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770), in particular an NTC thermistor, effective in thermal contact with at least a portion of the upper surface of the dry side of the carrier unit, the method comprising: receiving, at the controller, an activation signal (S1) to activate the heating system component; performing a test routine on the at least one temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770); and if the test routine is unsuccessful: entering a safe state (16) of the heating system component.

Description

[0001] This application is a divisional application of the Chinese patent application entitled “Method for controlling heating system components and heating system components”, application number 201910337748.3, and application date April 25, 2019. Technical Field

[0002] The invention relates to a method of controlling a heating system component for heating a fluid medium in a heating system for a household appliance. In addition, the invention relates to a heating system comprising a controller and at least one temperature sensor. Background Art

[0003] For many types of household appliances or household machines, it is necessary to heat a fluid medium, such as water. The heating can be caused by one or more heating systems. To this extent, a medium circuit can be provided, in which a pump is arranged to circulate the medium in the circuit.

[0004] A fundamental aspect of such a heating system is that, like all other components of the medium circuit, the system takes up only a small amount of space and is inexpensive to produce. Furthermore, the heating system should be easy to assemble. Reliable protection of the heating system must be guaranteed in the event of critical operating conditions that could cause plastic parts within the household appliance to melt or catch fire. In the case of some household appliances, it may also be necessary to prevent the medium to be heated from exceeding a predetermined temperature. For example, in the case of a dishwasher, it may be necessary to prevent the wash water from exceeding its boiling temperature.

[0005] US patent application 2006 / 0236999 discloses a heating system for heating a fluid medium, in particular for a household appliance, comprising a carrier unit, a heating unit arranged on the carrier unit, and a heat transfer element arranged on the carrier unit and comprising a material that is a good heat conductor. On the heat transfer element, a temperature safety device is mounted by a fixing element through a corresponding through hole.

[0006] A system with two temperature sensors for shutting down a device in the event of a fault is disclosed in DE patent application 102011002861. A similar system is also disclosed in DE patent application 102016215266.

[0007] DE patent application 10201220315 discloses a system with a pump, which comprises a safety control for switching off the pump. In the event of a fault, the safety control can also switch off the heating unit.

[0008] Furthermore, from EP patent application 3238599 a heating unit is known comprising an electronic temperature sensing device arranged thermally conductively with a heat conducting element to detect and record the temperature of the heat conducting element over time in order to provide information on the operating conditions of the washing machine. The device is used to avoid reaching the triggering temperature of the fuse.

[0009] A general aim in manufacturing heating systems and heating system components is to provide smaller and more compact structural components which provide sufficient heating power (if not the same heating power as before). Another aim is to reduce manufacturing costs.

[0010] In addition, when using a conventional temperature monitoring and / or control element (e.g., a thermal fuse) with a continuous flow water heater, there is a problem when the temperature monitoring and / or control element is fixed to a mounting plate with, for example, one or more screws. That is, when the mounting plate is welded to the heating unit, it may bend. In addition, when the corresponding fixing screws are tightened on the temperature monitoring and / or control element, the temperature monitoring and / or control element can be lifted from the fixing plate and held in the air above the hot position. Therefore, the maximum heat in the center of the heating unit cannot be released directly to the temperature monitoring and / or control element, but must be released through, for example, the mounting plate, screws and / or base plate flange. These effects lead to an unacceptable (i.e., too slow) response time of the temperature monitoring and / or control element. Therefore, it is advantageous to mount the temperature sensor directly at the location where a certain temperature should be monitored. NTC thermistors are temperature sensors known in the art. However, relatively cheap NTC thermistors may not be continuously exposed to temperatures exceeding 85 to 125°C. Since the heating units of heating system components often reach temperatures above 100°C, inexpensive NTC thermistors are often not suitable for mounting directly on or near the heating units within the heating system components, thereby preventing a more compact design.

[0011] It is therefore an object of the present invention to provide a method of controlling and protecting components of a heating system which avoids the disadvantages of prior art heating systems. Summary of the invention

[0012] According to a first aspect of the invention, there is provided a method for controlling a heating system component of a heating system for heating a fluid medium, the heating system component comprising: a carrier unit; a heating unit coupled to the carrier unit; and a controller; wherein the carrier unit comprises a wet side and a dry side, wherein the wet side corresponds to a surface of the carrier unit configured to be in contact with the fluid medium, wherein the dry side is located on a surface opposite to the wet side. The heating system component further comprises at least one temperature sensor, in particular an NTC thermistor, wherein the temperature sensor is effectively in thermal contact with at least a portion of an upper surface of the dry side of the carrier unit and is electrically isolated therefrom. The method comprises: receiving a start signal at the controller to start the heating system component; performing a test routine on at least one temperature sensor; and if the test routine is unsuccessful: entering a safe state of the heating system component.

[0013] Thanks to this approach, a safe boot process can be achieved.

[0014] If there is no water in the pump housing present on the wet side, overheating of the plastic components may occur due to errors in the heating system. The prior art already uses temperature sensors to monitor the entire component during the entire operation. The present invention describes continuous safety protection during the start-up process and operation.

[0015] Therefore, it is expected that at least a test routine of at least one temperature sensor is performed before the heating system component is fully started. If the test routine is unsuccessful, a safe state of the heating system component is entered. The safe state in this case may include not supplying power to the heating unit. For example, a single operating device can be operated, in particular a fuse can be blown or a safety switch (e.g. a relay, an electronic switching device) can be cut off, so that power is not supplied to the heating unit of the heating system component. The heating system component or an appliance comprising the heating system component can still remain switched on, but preferably a fault signal is output, for example by a display showing a fault code. For example, a display of an appliance having a heating system component and performing the method can display an appropriate fault code or an operator's instruction on the display. It is also conceivable to show instructions on how to solve the problem.

[0016] If the test routine is successful, startup of the heating system components is preferably completed accordingly.

[0017] The heating unit may be any suitable heating unit and may have any suitable form. In a particularly preferred embodiment, the heating unit is recessed in a groove provided on the dry side of the carrier unit. In this case, the heating unit is preferably curved and may be similar to a C-shape. Other suitable forms include tubular heaters, free flow heaters, flat plate heaters, thick and thin film technology, rod-shaped heating elements, etc.

[0018] Preferably, at least one temperature sensor, in particular an NTC thermistor, is effectively in thermal contact with at least a portion of the upper surface of the dry side of the carrier unit, wherein a portion of the upper surface of the dry side of the carrier unit is arranged to be in contact with the fluid medium on the wet side, and preferably, wherein a portion of the upper side of the carrier unit is effectively thermally coupled to the heating unit and electrically isolated therefrom.

[0019] Effective thermal contact with at least a portion of the upper surface of the dry side of the carrier unit does require that the temperature sensor is in direct contact with the upper surface of the dry side of the carrier unit. However, effective thermal contact is to be understood as providing a thermal contact that allows the measurement of the fluid medium circulating on the wet side of the carrier unit. Therefore, the thermal contact should ensure that the measured temperature of the fluid medium mainly affects the wet side of the carrier unit. The temperature sensor can also measure the mixed temperature of the fluid and the heating unit. By providing a temperature sensor, in particular an NTC thermistor, effectively in thermal contact with at least a portion of the upper surface of the dry side of the carrier unit, wherein the at least a portion of the upper side of the carrier unit is effectively thermally coupled to the heating unit, it can be ensured that the temperature sensor is not exposed to temperatures exceeding the maximum temperature of the fluid circulating on the wet side of the carrier unit, which in most common household appliances is 85 to 125°C. At this temperature, universal and economical NTC thermistors can be used, which further enables a compact design of the heating system components while reducing the material budget.

[0020] Preferably, the test routine comprises sending a test signal from the controller to the at least one temperature sensor, preferably by using a heating element. The test signal may simply trigger a response of the temperature sensor to test whether it is still functional. When a temperature sensor is not functional, temperature control of the heating system components is not possible during operation and overheating of the heating system components may easily occur. In order to avoid such a state, it is preferably tested whether one or more temperature sensors are operating in a normal state, whereby a test signal is sent to at least one temperature sensor by using a heating element.

[0021] The above steps can be performed without powering the heating unit, or during operation when the heating unit is powered. In the second case, it may be preferred to switch off the heating unit for a short time and send a test signal when the heating unit is switched off.

[0022] Furthermore, it is preferred that the test routine comprises: powering the heating unit at a predetermined test power level for a predetermined test time period; obtaining a temperature test value measured by at least one temperature sensor; and comparing the obtained temperature test value with a predetermined temperature threshold. Preferably, these steps are performed during operation, such as when hot water is produced. Preferably, the temperature test value is obtained after a predetermined test time period has passed. Preferably, the temperature test value is further obtained after an additional delay time (heater off time) after the predetermined test time (heater on time) period has ended. That is, the test time period may be a first duration, and the temperature test value is obtained after a second duration, the second duration being longer than the first duration. This is beneficial because heating system components have a certain temperature rise time (equivalent dead time), which depends on system characteristics, such as the size, material and thermal conductivity of the components.

[0023] In the step of comparing the obtained temperature test value with a predetermined temperature threshold, it can be determined whether the heating process results in a temperature that is too high for a short predetermined test time period. Therefore, when the obtained temperature test value is above the threshold, a dry run fault may be the cause. Therefore, in this case, the test routine is considered unsuccessful and a safe state is entered. In the opposite case, when it is determined that the obtained temperature test value is below the predetermined threshold, the test routine is considered successful and the start-up of the heating system component can be completed. The normal operating state can be entered.

[0024] In a preferred embodiment, the test power level is 100% or less of the maximum power level, preferably 50% or less, particularly preferably 25% or less. When the test power level is set relatively high, such as 100% of the maximum power level, a fast test result can be achieved. The heating unit is driven by the maximum power level, which is the maximum power level that the system can provide to the heating unit, thereby achieving a fast heating process.

[0025] However, setting the test power level to such a high value carries the risk of causing overheating of individual elements or other adjacent components. Therefore, it is also preferred to set the test power level to 50% or less of the maximum power level. When the heating unit is powered by alternating current, values ​​of 50%, 25% or less are easily obtained. In addition, a value of 25% or less reduces the risk of overshoot.

[0026] In another preferred embodiment, the test power is provided in a pulsed manner. Pulsing the test power is an effective way to reduce power levels and thus improve the safety of the heating system components. In the present case, the pulsed test power may include phase angle control, leading and trailing edge phase control, pulse packing control and / or pulse width modulation. Depending on whether direct current or alternating current is used, different pulse methods are preferred.

[0027] According to another preferred embodiment, the test routine includes powering the heating unit at a predetermined test power level at a test start time; obtaining a temperature test value measured by at least one temperature sensor; determining that a predetermined test temperature threshold is reached at a test end time; and comparing the duration from the test start time to the test end time with a predetermined time period threshold. These steps can be performed as an alternative or in addition to the above steps of the test routine, which includes powering the heating unit at a predetermined test power level for a predetermined test time period. In this alternative, the test time period is variable and the heating unit is powered at least until the test temperature threshold is reached. Therefore, in this embodiment, the duration to reach the temperature threshold is measured. When this duration is relatively long, it indicates that there is water on the wet side of the carrier unit. On the other hand, when this time period is relatively short, it indicates that there is no or only some water on the carrier unit, thus indicating a risk of dry running. Therefore, when it is determined that the duration from the test start time to the test end time is lower than the predetermined time period threshold, the test routine is considered unsuccessful and a safe state of the heating system component is entered. One benefit of this embodiment is that the temperature sensor can be designed in a simple manner. It is not important that the temperature sensor is capable of measuring a variety of different values; instead, it is sufficient when the temperature sensor is adapted to measure only one value, namely the test temperature threshold. Furthermore, in both cases a gradient can be calculated, in this case the temperature over time gradient (T / t), based on which a specific action can be taken.

[0028] Preferably, after a predetermined maximum time, in this embodiment, the power supply is stopped. Additionally or alternatively, the power supply is stopped at or within a short time after the test end time. Shortly thereafter, in the present case, it may include: within a predetermined time range after the test end time. The predetermined time range may be a set absolute duration or a relative duration depending on the duration from the test start time to the test end time, the measured temperature or the power supply. Limiting the power in this embodiment to a predetermined maximum time increases the safety of the heating system components and prevents overheating only by the test routine. In addition, it may be considered to stop the power supply shortly thereafter, for example within 1 second or 10 seconds after reaching a predetermined test temperature threshold. This may avoid false signal detection, and verification measurements may be performed in addition. It may be provided that the test temperature threshold needs to be exceeded for a period of time to trigger the corresponding signal. This may avoid false signal detection.

[0029] In another preferred embodiment, the test routine includes: powering the heating unit at a predetermined heat. In this alternative, the heat is kept constant.

[0030] Therefore, the method preferably further comprises: in this embodiment, determining the supply voltage of the heating unit; and calculating, by the controller, the start-up supply time required to obtain the supply of the predetermined heat. The supply time ts can be calculated by the following equation:

[0031] ts = W*R / U2; (Equation 1)

[0032] Thus, by knowing the resistance R and by measuring the supply voltage U, the time ts required to reach a predetermined amount of heat (work) W can be determined. An advantage of this embodiment is that the amount of supplied heat for performing the test routine is always the same. The risk of overheating is reduced.

[0033] In another preferred embodiment, a plurality of temperature test values ​​are obtained, and the method further comprises the step of calculating a heating curve based on the plurality of temperature test values. To calculate the heating curve, it is not necessary to perform continuous or quasi-continuous temperature measurements, but it is sufficient to obtain a plurality of temperature test values ​​at discrete times. In one embodiment, it is sufficient to obtain only two temperature test values ​​to calculate the heating curve.

[0034] Based on such a heating curve, a slope of the heating curve may be determined and the determined slope may be compared with at least a first predetermined slope threshold. In this respect, it should be noted that a relatively high difference quotient T / t indicates rapid heating and thus may indicate a lack of water on the wet side.

[0035] For some embodiments and applications, it is preferred that the heating system component comprises a second temperature sensor remote from the first temperature sensor. For example, the first temperature sensor may be installed in a so-called hot zone close to the heating unit and the second temperature sensor may be installed in a cold zone far from the heating unit. One of the first and second temperature sensors may also be installed between the hot zone and the cold zone, in a so-called mixed zone.

[0036] It should be noted that even though NTCs are preferred as temperature sensors, other known devices may also be used, such as SMD-NTCs, thin film thermistors, thermocouples or resistance temperature sensors.

[0037] When two temperature sensors are used, it may be beneficial for some applications that the method further comprises: obtaining a second temperature test value measured by the second temperature sensor; and comparing the obtained second temperature test value with a second predetermined temperature threshold. Preferably, the other steps described above are also performed using a second temperature sensor.

[0038] Furthermore, the controller can be connected to at least one temperature sensor via a main connection and to a redundant second temperature sensor by using a redundant connection. Some regulations require a redundant system using two measuring paths. The system can be designed to be redundant. Safety is further increased.

[0039] In a second aspect of the invention, the purpose stated in the introduction is also solved by a heating system component of a heating system for heating a fluid medium, wherein the heating system component comprises: a carrier unit; a heating unit connected to the carrier unit; and a controller; wherein the carrier unit comprises a wet side and a dry side, wherein the wet side corresponds to a surface of the carrier unit configured to be in contact with the fluid medium, wherein the dry side is located on a surface opposite to the wet side, and wherein the heating unit is recessed in a groove arranged on the dry side of the carrier unit, and further comprises at least one temperature sensor, in particular an NTC thermistor, wherein the temperature sensor is effectively in thermal contact with at least a portion of the upper surface of the dry side of the carrier unit, wherein the controller comprises a memory and a processor, the memory comprising software code which, when run on the processor, causes the controller to perform a method according to any one of claims 1 to 12.

[0040] The controller is not necessarily directly adjacent to the carrier unit; the controller may also be the controller of a heating system or a higher system, such as a system of an appliance, which uses the heating system. It may also be provided that the controller is accessible via a network or the Internet in order to read a specific temperature sensor value stored in the memory. Furthermore, the controller may be accessible via the Internet in order to update software stored on the memory or to initiate other actions. Prior to this action, temperature sensor data of various other heater units, such as a dishwasher, may also be collected via the Internet.

[0041] In addition, it should be understood that the controller including the memory, the processor and the software code is also separately and independently claimed herein.In addition, the software code can also be independently and independently claimed, and the method of the first aspect of the present invention is performed when the software code is executed on the processor.

[0042] In one embodiment, the heating system further comprises a heat conducting plate covering at least a portion of the groove, wherein the heat conducting plate comprises a separation portion at a circumferential portion, which is separated from the heating unit recessed in the groove, the separation portion having a protruding portion extending beyond the groove of the carrier unit, the protruding portion being in direct contact with the dry side of the carrier unit; the temperature sensor is mounted on the protruding portion, and wherein the separation portion of the heat conducting plate preferably comprises a groove in a radial direction of the corresponding peripheral edge of the protruding portion. Preferably, the heating system component may further comprise a second temperature sensor, in particular an NTC thermistor, wherein the second temperature sensor is in thermal contact with the upper surface of the heating unit in the covering groove of the heat conducting plate or is directly located on the heating surface.

[0043] In another embodiment, the temperature sensor is arranged in a groove of the carrier unit shielded from the heating unit by a shielding unit. Preferably, the shielding unit is made of coated steel, stainless steel or aluminum material. In a further preferred embodiment, the second temperature sensor is arranged in a groove shielded from the heating unit by the shielding unit, wherein the resulting temperature is first measured by the first and second raw temperature values ​​and then derived from them by a mathematical formula (such as minimum, maximum, average...). In a further preferred embodiment, the first and second temperature sensors are NTC thermistor pellets cast in epoxy resin between the dry side of the carrier unit and the shielding unit. The compact and cost-effective design provided by this embodiment allows reliable measurement of the fluid temperature on the wet side of the carrier unit while providing easy assembly of the heating system components in the corresponding household appliance. Since the temperature measuring component is arranged in the groove, the risk of damage during assembly is significantly reduced.

[0044] In one embodiment, the heating system component further comprises a heat conducting plate covering at least a portion of the recess, wherein the heat conducting plate comprises a protruding portion extending beyond the recess of the carrier unit, the protruding portion being in direct contact with the dry side of the carrier unit; and wherein the temperature sensor is arranged on a ceramic pad fixed to the protruding portion of the carrier unit. Preferably, the second temperature sensor is located on a second ceramic pad, wherein the second ceramic pad is fixed at a position where the heat conducting plate covers the recess. In a further preferred embodiment, one or more conductor paths are arranged along the heat conducting plate to connect the one or more temperature sensors, wherein the conductor paths are insulated from the heat conducting plate by an insulating layer, preferably comprising a polyimide, such as but not limited to Kapton, polyamide or polyester.

[0045] In another embodiment, the heating system component further comprises a heat conducting plate covering at least a portion of the groove, wherein the heat conducting plate comprises a protruding portion extending beyond the groove of the carrier unit, the protruding portion being in direct contact with the dry side of the carrier unit; wherein at least a portion of the heat conducting plate is covered with an insulating layer, on top of which a temperature sensor and a conductor path connected to the temperature sensor are formed. Preferably, the heating system component comprises a plug with a pin connected to the conductor path, wherein the plug also provides an electrical connection for the heating unit. Preferably, the temperature sensor, the conductor path and the insulating layer are formed on the heat conducting plate by printing or thermal spraying. Alternatively, the insulating layer can also be directly attached to a portion of the dry side of the carrier unit. Preferably, the temperature sensor and the conductor path are formed at the insulating layer before being attached to the carrier unit. The insulating layer can be connected to a corresponding plug and then bonded to the carrier unit, wherein the plug can be connected (e.g., welded, soldered, etc.) to the heating unit connection pin and / or the carrier unit.

[0046] In another embodiment, the carrier unit comprises an undercut portion, which is covered with a thermoplastic layer, the thermoplastic layer being doped with a metal-plastic additive sprayed directly at the undercut portion and subsequently metallized at a corresponding portion of the upper surface of the thermoplastic layer; wherein the temperature sensor and the conductor path connected to the temperature sensor are formed on the metallized thermoplastic layer by laser cutting. Preferably, the heating system component comprises a transparent plug, the transparent plug comprising electrical contacts connected to the conductor path leading to the temperature sensor, wherein the transparent plug is coupled to the thermoplastic layer using laser welding.

[0047] In one embodiment, the heating system component further comprises a heat conducting plate covering at least a portion of the recess, wherein the heat conducting plate comprises a protruding portion extending beyond the recess of the carrier unit, the protruding portion being in direct contact with the dry side of the carrier unit; wherein at least a portion of the heat conducting plate is covered with a metal-plastic additive doped directly sprayed at at least a portion of the protruding portion and subsequently metallized at a corresponding portion of the upper surface of the thermoplastic layer; wherein the temperature sensor and the conductor path connected to the temperature sensor are formed on the metallized thermoplastic layer by laser cutting. Preferably, the heating system component comprises a transparent plug comprising an electrical contact connected to the conductor path leading to the temperature sensor, wherein the transparent plug is coupled to the thermoplastic layer using laser welding.

[0048] It shall be understood that a preferred embodiment of the invention can also be any combination of the dependent claims or the above-described embodiments with the respective independent claim.

[0049] It must be noted that the present invention can also be used in combination with quartzite heaters, flow-through heaters, flat plate heaters, thick film and thin film heaters.

[0050] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In the following figures:

[0052] Figure 1 Embodiments of heating system components are shown schematically and exemplarily;

[0053] Figure 2a and 2b Schematically and exemplarily shows Figure 1 A cross-sectional view of a heating system component;

[0054] Figure 3 An embodiment of a method for controlling a heating system component is schematically and exemplarily shown;

[0055] Figure 4 An embodiment of a controller is shown schematically and exemplarily;

[0056] Figure 5a A first diagram schematically and exemplarily shows a heating process;

[0057] Figure 5b A second diagram schematically and exemplarily showing a heating process;

[0058] Figure 6a and 6b Another embodiment of a heating system component is schematically and exemplarily shown;

[0059] Figure 7 Another embodiment of a heating system component is schematically and exemplarily shown;

[0060] Figure 8a and 8b Another embodiment of a heating system component is schematically and exemplarily shown;

[0061] Figure 9a and 9b Another embodiment of a heating system component is schematically and exemplarily shown;

[0062] Fig.10 Another embodiment of a heating system component is schematically and exemplarily shown;

[0063] Figures 11a to 11c Another embodiment of a heating system component is schematically and exemplarily shown; and

[0064] Fig.12 Possible temperature measurement points on heating system components are shown schematically and exemplarily. DETAILED DESCRIPTION

[0065] Figure 1 An embodiment of a heating system component 100 is schematically and exemplarily shown. The heating system component 100 comprises a carrier unit 110 and a heating unit 120.

[0066] The heating system component 100 can be connected to, for example, a delivery pump of a household appliance (such as, but not limited to, a dishwasher). The heating system component 100 can be attached to the delivery pump or the delivery pump housing during assembly of the household appliance. In another example, the heating system component 100 can form a preassembled structural unit with the delivery pump.

[0067] from Figure 1 As can be seen in the figure, the carrier unit 110 is a circular disk. In a concentric relationship with its central axis (not shown), the carrier unit 110 has a circular hole 111, through which the suction pipe of the delivery pump passes with sealing integrity relative to the medium. At its peripheral edge, the carrier unit 110 can be engaged on the edge of the delivery pump housing with sealing integrity relative to the medium. Figure 1 As shown, the back side of the carrier unit 110 is in direct contact with the medium to be heated in the installed state of the pump and can therefore be referred to as the wet side 101. Figure 1 The side of the carrier unit 110 shown in FIG. 1 is not in contact with the medium and can therefore be referred to as the dry side 102 .

[0068] The heating unit 120 is arranged on the dry side 102 of the carrier unit 110, such as Figure 2a As shown, it shows that along Figure 1 The heating unit 120 is coupled to the carrier unit 110 through a coupling step. The coupling step may include any one of a welding step, a laser welding step, a gluing step, an ultrasonic welding step, and / or a friction welding step.

[0069] The carrier unit 110 may include a composite material. The composite material includes at least an aluminum layer and a stainless steel layer. The stainless steel layer is arranged on the wet side 101 of the carrier unit 110. The aluminum layer is arranged on the dry side 102 of the carrier unit 110. In an example, the composite material may be produced by a cold roll bonding process.

[0070] exist Figure 1 In the illustrated embodiment, the carrier unit 110 further includes a groove 112. The groove 112 is configured to receive the heating unit 120. The heating unit 120 includes a first cross section perpendicular to the axial direction of the heating unit 120. The first cross section may be a rectangle, a cap-shaped trapezoid with rounded edges, or a bell-shaped trapezoid with rounded edges.

[0071] exist Figure 1 In the embodiment shown, the cross section of the groove 112 corresponds to the first cross section of the heating unit 120. Specifically, the heating unit 120 is arranged in the groove 112, such as Figure 2a The cross-section of the groove 112 and the cross-section of the heating unit 120 are selected so that at least a portion of the surface of the heating unit 120 and a portion of the dry side 102 form a flat surface. Figure 2a In the embodiment, all three sides of the heating unit 120 are welded or brazed to the surface of the groove 112 of the carrier unit 110. The necessary close contact between the surfaces of the heating unit 120 and the carrier unit 110 can be achieved by applying a pressure preload to the heating unit 120 during the coupling step. Optionally, a thermally conductive paste 122 can be applied to one or both surfaces of the carrier unit 110 and the heating unit 120. By using a thermally conductive paste, problems associated with the presence of a gap between the carrier unit 110 and the heating unit 120 can be avoided.

[0072] Another possibility to solve the problem associated with the occurrence of gaps between the carrier unit 110 and the heating unit 120 is to arrange a phase change compound between the carrier unit 110 and the heating unit 120. Such a compound changes its phase above its phase change temperature and is thus able to fill cracks, gaps, crevices, etc. In one embodiment, the phase change compound is applied to the surface of the carrier unit 110 and / or the heating unit 120 by a dispensing step. Dispensing generally means that the phase change compound dries in a short time.

[0073] exist Figure 1 In the embodiment shown, the heating system component 100 further comprises a temperature sensor 170a, preferably an NTC (negative temperature coefficient) thermistor, which can be connected to a processing unit of the household appliance, in particular a controller 30 as described below, in order to measure the temperature of the fluid circulating on the wet side of the heating system component 100. NTC thermistors provide a cost-effective method for determining temperature. However, such common, inexpensive NTC thermistors only maintain continuous operation in a temperature range of up to 100°C. Since the heating unit 120 typically reaches temperatures above 100°C, the NTC thermistor 170a must be thermally shielded from the heating unit 120 to ensure a certain durability while avoiding the use of more expensive NTC thermistors that withstand higher temperatures. Therefore, the heating unit 120 is covered by a heat conducting plate 140 at the peripheral portion of the carrier unit 110 covering the groove 112. The heat conducting plate 140 may include a protruding portion 141 extending toward the inner circumferential portion 113 of the carrier unit 110. The protruding portion 141 is in direct contact with the dry side 102 of the carrier unit 110. Since the fluid circulates in operation at the opposite side of the carrier unit 110, the wet side 101, the temperature of the carrier unit 110 and thus the temperature of the protruding portion 141 of the heat conducting plate 140 approximately reflects the temperature of the fluid. In order to measure the temperature of the fluid, the NTC thermistor 170a is therefore mounted at the protruding portion 141 of the heat conducting plate 140. In order to control the heat transfer from the heating unit 120 to the protruding portion 141 where the NTC is mounted, the heat conducting plate 140 may provide a separation portion 142 at the peripheral portion above the heating unit 120 at the same angle as the protruding portion 141 extending toward the center. Figure 2b Shown along Figure 1 Cross-sectional view along line BB in FIG. Figure 2bIt is shown that there is a space between the separated portion 142 of the heat conducting plate 140 and the heating unit 120. The protruding portion 141 is in contact with the separated portion 142, but is inclined toward the upper surface of the carrier unit 110. Preferably, the angular expansion of the separated portion 142 is slightly wider than the angular expansion of the protruding portion 141. The heat conducting plate 140 may be further provided with grooves 143 at the separated portion 142, which are provided toward both sides of the angular expansion of the separated portion 142, wherein the length of the grooves 143 affects the heat conducted from the unseparated portion 144 of the heat conducting plate 140 to the protruding portion 141.

[0074] Optionally, a second NTC thermistor may be provided at the other separated portion 142 in order to determine the fluid temperature, so that the first and second NTC thermistor measurements may be averaged to increase reliability. Alternatively, the second NTC thermistor 170b may be mounted at the non-separated portion 144 of the heat conducting plate 140 in order to determine the temperature of the heating unit 120 itself, in order to prevent, for example, dry running of the pump. In the latter case, an NTC thermistor must be selected that maintains the final temperature achievable by the heating unit 120.

[0075] When the heating unit 120 is powered on, it may happen that there is no water at the wet side 101, which may lead to rapid overheating of the heating system components. According to the present invention, at least one temperature sensor 170a, 180a, 270a, 370a, 460, 470a, 480, 770 is used to determine whether a heating system component is overheated or whether safe operation is possible. In this regard, Figure 3 A method 1 for controlling a heating system component 100 is shown. Figure 3 The method 1 shown in FIG. 1 basically comprises three parts, wherein in the first part a receiving step 2 is performed. In the receiving step 2, a start signal S1 (see FIG. 1 ) is received at the controller 30 for starting the heating system component 100. Figure 4 ). The controller 30 may be a controller of an appliance using the heating system component 100. In the case of a start test, for example, the start signal S1 is typically a signal provided by, for example, a start switch, which may be manually operated by a user, or an automatically generated signal provided by a higher level control.

[0076] When the start signal S1 is received in the receiving step 2, the test routine 3 as the second part is then executed. It should be noted that there are generally three different options for executing the test routine 3. The first option is to execute the test routine 3 on demand without any further heating step. The second option is to execute the test routine 3 after starting the appliance. The third option is to execute the test routine 3 during normal operation of the appliance. It should be understood that all three options are within the scope of the present invention, even if only the second option is described in detail in the embodiments described below.

[0077] According to this embodiment ( Figure 3 ), in test routine 3, the operation of at least one temperature sensor 170a, 180a, 270a, 370a, 460, 470a, 480, 770 is first tested, wherein in sending step 4, a test signal S2 is sent from the controller 30 to at least one temperature sensor 170a, 180a, 270a, 370a, 460, 470a, 480, 770. The test signal S2 (see Figure 4 ) is sent from the controller 30 to at least one temperature sensor 170a, 180a, 270a, 370a, 460, 470a, 480, 770 and the temperature sensor 170a, 180a, 270a, 370a, 460, 470a, 480, 770 may respond with a corresponding response signal S2R indicating that it is functioning normally. When the response signal S2R is received, the test routine 3 may be further executed. According to this embodiment ( Figure 3 ), then the power supply step 6 is performed, and the power supply is supplied at a predetermined test power level Wt (see Figure 5a ) supplies power to the heating unit 120 for a predetermined test period Th. The test period Th is Figure 5a , which is also described in detail below. Therefore, the controller 30 sends the power S3 to the heating unit 120 for a short time of the test period Th. The predetermined test power level Wt is preferably 50% or less.

[0078] When the test power level Wt is 50% or less of the maximum power level, the risk of overheating is reduced only in test routine 3. Other preferred values ​​are 20% or less, 25% or less, 40% or less. Preferably, the test power level Wt is not lower than 10%, because then the test routine 3 will not provide accurate results.

[0079] After the heating unit 120 has been powered at the test power level Wt for a predetermined test period Th (see Figure 5a ), the temperature test value S4 is measured by at least one temperature sensor 170a, 180a, 270a, 370a, 460, 470a, 480, 770. The step 8 of determining is preferably performed at a determining time Td, which is slightly later than the end of the test time period Th, such as from Figure 5a This means that after the test period Th has passed, it is preferred to wait for a short time (e.g., 1 to 10 seconds) because the heater unit 120 has a heater lag time and responds in a delayed manner. In order to take this heater lag time into account, a determination step is performed at a determination time Td.

[0080] Furthermore, in the comparison step 10, the obtained temperature test value S4 is compared with a predetermined temperature threshold value Tt (see FIG. 1 ) according to the heating time Th, the determination time Td, the test power level Wt, and the overall structure of the heater unit 120 (particularly the heater hysteresis time). Figure 5a ) for comparison.

[0081] exist Figure 5a 5 , the temperature curve shown in the lower graph 40 is typical for a heater unit 120 with sufficient water on the wet side 101. The temperature curve shown in the upper graph 42 in FIG. 5 is typical for a heater unit 120 without sufficient water on the wet side 101 and with a risk of dry running. It can be inferred from FIG. 5 that during the heating time Th, the graph 42 is steeper than the graph 40. At a determined time Td, the temperature is measured using at least one temperature sensor 170a, 180a, 270a, 370a, 460, 470a, 480, 770. For the graph 40, a temperature value Tf is determined, which is below a predetermined temperature threshold value Tt. For the graph 42, a temperature Te is determined, which is above a predetermined temperature threshold value Tt.

[0082] Based on this comparison, a decision 12 is made after executing the test routine 3. When the determined temperature value is below a predetermined temperature threshold Tt, such as value Tf, the test routine 3 is determined to be successful and the normal start-up process can be continued in step 14. Normal operation of the heating unit 120 is performed.

[0083] When, in decision step 12 , the measured temperature value is found to be higher than a predetermined temperature threshold Tt (for example a value Te), the test routine 3 is considered unsuccessful and a safe state 16 is subsequently entered.

[0084] Such a safe state may be, for example, cutting off the power supply to the heating unit 120 while the appliance is still switched on. The test result signal S5 may be provided by the controller 30 to an operator, or to a higher level control unit of the appliance.

[0085] Figure 5b An alternative graph is shown which illustrates an embodiment of the slope of a first heating curve 44 using a first temperature sensor and a second heating curve 46 using a second temperature sensor. Figure 5bIn the embodiment, the first temperature sensor is represented by NTC1 and the second temperature sensor is represented by NTC2, even though the first temperature sensor may be any one of the temperature sensors 170a, 180a, 270a, 370a, 460, 470a, 480, 770, the second temperature sensor may be any one of the temperature sensors 170b, 180b, 270b, 370b, 470b, 480 (located near NTC1), 770 (located near NTC1). For example, the first temperature sensor NTC1 may be preferably installed in the first installation position 840 (or 842), and the second temperature sensor NTC2 may be preferably installed in the second installation position 842 (or 844), as shown in FIG. Fig.12 As shown, it will be described in more detail below.

[0086] First Example - Dry Run Failure

[0087] In a first example, two temperature sensors NTC1, NTC2 can be used to detect dry-running faults. For this application, two temperature sensors NTC1, NTC2 are required to achieve redundancy. In this example, the method preferably includes determining a first slope Y1 of a first heating curve 44 of a first temperature sensor NTC1. The first slope Y1 is defined by ΔT / Δt measured starting at a determined time Td. Then, the determined first slope Y1 is compared with a first slope threshold YT1, which can be in the range of 12 to 40 K / s, depending on the physical inertia of the heating unit 120. Preferably, the method also includes determining a second slope Y2 of a second heating curve 46 of a second temperature sensor NTC2. The second slope Y2 is defined by ΔT / Δt measured starting at a determined time Td. Then, the determined second slope Y2 is compared with a second slope threshold YT2, which can be in the range of 1 to 10 K / s, depending on the physical inertia of the heating unit 120, because the second mounting position 842 is located in the mixing area, so it is assumed that the temperature rise is slower.

[0088] Furthermore, the method may include determining a difference T having a predetermined threshold value NTC1 –T NTC2 , where T NTC1 is the temperature measured at a certain time Td using the first temperature sensor NTC1, T NTC2 is the temperature measured at the determined time Td using the second temperature sensor NTC2. In this case, the threshold value may be in the range of 80 to 120°C. Of course, a comparison with a fixed predetermined threshold value of only one temperature test value may also be provided. For example, it may be determined whether the temperature test value of the first temperature sensor NTC1 is higher than a predetermined threshold value in the range of 180 to 220°C.

[0089] If one or more of the above four tests are positive, ie the corresponding value is above the corresponding threshold value, then test routine 3 is unsuccessful.

[0090] Example 2 - Boil to dryness

[0091] In a second example requiring two temperature sensors, a so-called boil-to-dry process is performed. During the boil-to-dry process, the heating unit is started while there is a maximum water level on the wet side. The heating unit is then powered until all the water is boiled and the wet side is dry. Such a process can be advantageously performed, for example, with an electric kettle.

[0092] During this process, similar steps as defined in the first example above are performed, but using the following thresholds:

[0093] - Second slope Y2 (ΔT / Δt); Second slope threshold YT2: 1-10K / s

[0094] -First slope Y1 (ΔT / Δt); first slope threshold YT1: 12-40K / s

[0095] -T NTC1 –T NTC2 ;Threshold: 80-120℃;

[0096] -Temperature test value NTC1: 180-220℃.

[0097] Example 3 - Calcification / Scaling

[0098] In this process, similar steps as defined in the first example above are performed. This process is performed to test for the presence of lime on the surface of the heating system component 100. The following thresholds are used:

[0099] In the process, the method preferably includes determining a difference T having a predetermined threshold value NTC1 –T NTC2 steps, where T NTC1 is the temperature measured at a certain time Td using the first temperature sensor NTC1, T NTC2 is the temperature measured at the determined time Td using the second temperature sensor NTC2.

[0100] However, the determined difference is preferably compared with a first lime threshold value YL1 and a second lime threshold value YL2. The first lime threshold value YL1 may be in the range of <50 to 60°C. The second lime threshold value YL2 may be in the range of 80 to 120°C. When the determined difference is between the two lime threshold values ​​YL1, YL2, it may indicate the presence of lime on the surface (wet side 101) of the heater unit 120. A corresponding notification may be given to the operator.

[0101] When the second threshold is exceeded, this may indicate that a relatively high amount of lime is present at the heater unit 120 and the test routine 3 is deemed unsuccessful. In this case the safe state 16 may be entered.

[0102] One of the two temperature sensors NTC1 , NTC2 can be designed as a safety-related sensor, while the other can be designed as a non-safety-related sensor.

[0103] Example 4 - Dry running with only one temperature sensor

[0104] In this fourth example, a dry run fault may be detected based on the first or second temperature sensor NTC1, NTC2. The method in this embodiment preferably includes determining a first slope Y1 of a first heating curve 44 of the first temperature sensor NTC1. The first slope Y1 is defined by ΔT / Δt measured starting at a determined time Td. The determined first slope Y1 is then compared with a first slope threshold YT1, which may be in the range of 15 to 40 K / s, depending on the physical inertia of the heating unit 120.

[0105] In a second step, the absolute temperature test value at a determined time Td is measured and compared with a corresponding threshold value. In this case, the threshold value may be in the range of 180 to 220°C.

[0106] Alternatively, a second temperature sensor NTC2 is used. In this case, the corresponding threshold values ​​for the difference and absolute temperature test values ​​are: 1 to 10 K / s and 80 to 120°, respectively.

[0107] When both the threshold value of the difference and the threshold value of the absolute temperature test value are exceeded, the test routine 3 is deemed unsuccessful and the safe state 16 is entered.

[0108] Example 5 - Boiling to Dryness with Only One Temperature Sensor

[0109] This process is performed in the same manner as in the fourth example.

[0110] Example 6 - Calcification with only one temperature sensor

[0111] In this example, only the absolute temperature test value measured at the determination time Td is used. The threshold value of the first temperature sensor NTC1 may be set to 120 to 150°C, and the threshold value of the second temperature sensor NTC2 may be set to 60 to 80°C.

[0112] In an alternative, the process of the sixth example is performed using an additional temperature sensor that is already present in the appliance using the heating system component. With the help of this additional sensor, the temperature of the water can be accurately determined, and by this additional value, the amount of lime can be appropriately determined.

[0113] Furthermore, preferably, the method in this embodiment comprises the following steps: storing the measured temperature test value in a memory of the controller; and comparing the measured value with at least one previously stored value, preferably with a plurality of previously stored values.

[0114] Previously stored values ​​can be used to calculate a curve and the slope of this curve can also be used to perform lime analysis at the heater unit. Depending on the slope, specific notifications can be provided to the operator.

[0115] Example 7 - Calcification with a Temperature Sensor

[0116] The seventh example is based on the fourth example and is again used to determine lime.

[0117] In this embodiment, the second temperature test value is obtained after an additional waiting time after the determination time Td.The additional waiting time is preferably chosen such that the temperature measured by the first and / or second temperature sensor NTC1 , NTC2 is substantially equal to the temperature of the water present on the wet side.

[0118] This second value may then be used as described in the third example.

[0119] FIGS. 6 to 9 now show further variants and embodiments of a heating system component 100 and in particular different positions for mounting at least one temperature sensor.

[0120] exist Figure 6a In the embodiment schematically shown in , a heating system component 100 is shown, which provides one or more temperature sensors, preferably NTC thermistors 180, in a groove 112. The heating unit 120 inserted into the groove 112 of the carrier unit 110 provides connecting pins 123 at both ends of the heating unit 120. These connecting pins 123 are not located in the groove 112, but protrude in the axial direction to be connected to a power source. Therefore, the temperature sensor 180 is preferably arranged in a portion of the groove 112 that is not covered by the heating unit 120 and is located below the connecting pins 123. In order to shield the temperature sensor 180 from the heating unit 120, a shielding unit 181 is arranged inside the groove 112 and is preferably shape-fitted to the wall of the groove 112. The shielding unit 181 is made of a heat-insulating material, such as but not limited to stainless steel. As Figure 6bAs shown in the cross-sectional view of , the shielding unit 181 provides a hollow chamber 182, into which a temperature sensor 180a, preferably in the form of an NTC pill, is inserted. In order to fix the NTC thermistor in the hollow chamber 182, an epoxy resin is injected into the chamber 182, preferably a temperature-resistant two-component resin. Likewise, optionally, a second NTC thermistor 180b can be arranged in the hollow chamber 182 in order to determine the average temperature of the fluid circulating at the wet side 101 of the carrier unit 110. The compact and cost-effective design provided by this embodiment allows reliable measurement of the fluid temperature on the wet side 101 of the carrier unit 120, providing easy assembly of the heating system component 100 in the corresponding household appliance. Since there are no components protruding from the dry side of the carrier unit, the risk of damage during assembly is significantly reduced.

[0121] Figure 7Another embodiment is schematically shown, in which one or more NTC thermistors 270a, 270b are arranged at respective pads 250a, 250b made of ceramic material. Each pad 250a, 250b is fixed to a heat conducting plate 240 by a form-fit connection. The heat conducting plate 240 covers at least a portion of the inner circumferential portion 113 of the carrier unit 110, so that the NTC thermistor 270a mounted at the protruding portion 241 of the heat conducting plate 240 can measure the temperature of the water circulating at the wet side 101 of the carrier unit 110. Likewise, in the case where a second NTC thermistor 270b should be provided, the second NTC thermistor 270b can be located at another portion of the inner circumferential portion 113 of the carrier unit 110, or the heat conducting plate 240 can also cover at least a portion 244 of the recess 112 in which the heating unit 120 is embedded, so that in addition to the water temperature, the second NTC thermistor 270b can measure the temperature of the heating unit 120 itself. The conductive path 261 connecting the NTC thermistors 270a, 270b to an external processing unit (not shown) is electrically connected to the NTC thermistors 270a, 270b, wherein the NTC thermistors 270a, 270b and the conductive path 261 are covered by resin. The conductive path 261 is preferably guided along the heat conducting plate 240, wherein a thin insulating layer 260, preferably a thin foil, is provided between the conductive path 261 and the heat conducting plate 240. The thin insulating layer 260 is preferably made of polyimide Kapton. However, any other suitable polyimide, polyamide or polyester can be used instead. In a preferred embodiment, a single plug 300 can be used to provide power to the connecting pin 123 of the heating unit 120 through a corresponding pin 302, and provide a connection between the conductive path 261 from one or more NTC thermistors 270a, 270b and the external processing unit. Preferably, the heat conducting plate 240 is grounded through the plug assembly 300 via the corresponding connection 301. Likewise, the compact design provides advantages during assembly of the heating system component 100 within a superordinate component into which the heating system component 100 is integrated. Having a single plug 300 for connecting the heating unit 120 and the one or more temperature sensors 270a, 270b further reduces complexity during assembly and the required material budget.

[0122] Figure 8aThe embodiment schematically shown in also shows a heating system component 100 with a heat conducting plate 340, wherein at least a portion 341 of the heat conducting plate 340 is in direct contact with the dry side 102 of the carrier unit 110, and wherein one or more NTC thermistors 370a, 370b and a conductive path 361 are arranged thereon, with an insulating layer 360, preferably in the form of a thin foil, between the heat conducting plate 340 and the NTC thermistors 370a, 370b conductive paths 361. The insulating layer 360, the one or more NTC thermistors 370 and the corresponding conductive paths 361 are printed or sprayed onto the heat conducting plate 340 as a thin layer, wherein the insulating layer 360 (preferably made of a ceramic material) is a first layer, on top of which the NTC thermistors 370 and the corresponding conductive paths 361 are arranged. Likewise, the heating system component 100 can preferably be provided with a single plug 300, such as Figure 8b As shown, it is suitable for providing power to the connecting pin 123 of the heating unit 120, such as Figure 7 In addition, the plug 300 provides one or more connection pins 302 for connecting to the conductive path 361, such as by welding. Preferably, the heat conducting plate 340 is grounded through the plug 300 via the corresponding connection 301, such as Figure 7 361 and a ground connection to the side of the plug 300. Likewise, the compact design provides advantages during assembly of the heating system component 100 within a superordinate component in which the heating system component 100 is integrated. Having a single plug 300 for connecting the heating unit 120 and one or more temperature sensors 370 further reduces complexity during assembly and the required material budget.

[0123] Figure 9aAnother embodiment is schematically shown, in which one or more temperature sensors 470 are arranged at the inner circumferential portion of the carrier unit 110, wherein the carrier unit 110 includes an undercut portion 400, which is filled with a thermoplastic layer 500 by injection molding to form a substrate of a so-called molded interconnect device (MID). In a first step, the undercut portion 400 is provided with a microstructure by a thin laser beam. The thermoplastic is arranged on top of the microstructured surface of the metal layer. The metal layer is heated by a further laser beam while the thermoplastic is pressed against the microstructure at the surface to provide a hybrid metal-plastic connection. The thermoplastic layer 500 is doped with a metal-plastic additive, which can be activated by exposure to a laser beam. This process is generally referred to as metallization, in which two different parts are metallized, one for the temperature sensor 470, such as an NTC thermistor, and the other for the conductive path 461. The NTC thermistor 470 and the corresponding conductive path 461 are cut with a laser. Also in this embodiment, a form-fitting plug 600 is provided, which has a connecting pin 602 to connect to the corresponding conductive path 461. The housing of the plug 600 is preferably made of a transparent plastic material, which can be laser welded to the thermoplastic layer 500, which should therefore preferably be made of a thermoplastic material that absorbs the energy of the laser beam that previously passed through the transparent plug 600 housing without depositing a large amount of energy in the plastic material and thus deforming it. The form-fitting design provided by this embodiment makes it easy to assemble the heating system component 100 into a superordinate system and reduces the size and material budget required to implement the temperature sensor 470 for the heating system component 100.

[0124] Fig.10A further embodiment is schematically shown, in which one or more temperature sensors, in particular NTC thermistors 770, and conductor paths 761 between the one or more NTC thermistors 770 and the external plugs are formed on a thin layer 760, preferably a thin polymer foil, before the foil is attached to the carrier unit 110. The NTC thermistors 770 as well as the conductor paths 761 can be formed by printing, vapor deposition or metallization. Preferably, the sensor foil is pre-assembled with a suitable plug 600, which provides conductor pins for the conductor paths and preferably also provides a power connection for the heating unit and a pin for grounding the carrier unit. The plug 600 can then be mounted on the carrier unit 710 by welding, in particular spot welding power connections 302 and ground connections 301 to the heating unit 120 and the carrier unit 710, respectively. The thin foil 760 is then attached to the carrier unit 710 by gluing at least a portion of the underside of the foil 760 to the dry side of the carrier unit 110 using a heat-resistant glue material. The NTC thermistor is preferably located at a portion of the dry side of the carrier unit 110, whose wet side is in contact with the fluid circulating on the wet side. This embodiment allows to arrange the temperature sensor at the desired location of the carrier unit in a particularly flexible manner. In addition, this embodiment provides a very compact design without any protrusions or cables that require space and care during assembly.

[0125] Figures 11a to 11c Another embodiment of a heating system component 100 is shown, which further comprises a carrier unit 110 and a heating unit 120 attached thereto. Fig.11a In the overall view of FIG. 1 , the heating system component 100 can be seen attached to a pump housing 800, which can be assembled within the appliance. The heating system component 100 includes a main connector plate 802, which includes two male connectors 804 for the heating unit 120 and one male connector 806 for the temperature sensor 480, which will be referred to as Fig.11b , 11c The male connectors 804, 806 are connectable to a first female connector 808 for the heating unit 120 and a second female connector 810 for the temperature sensor 480. In this embodiment, the heating system component 100 includes only one single temperature sensor 480.

[0126] The two main connectors 408 for the heating unit 120 are basically formed at the heating unit connector frame 812, such as Fig.11b The frame 812 includes two male connectors 804 and first and second heating unit contacts 814a, 814b, which extend from the frame 812 and contact two corresponding end contacts 816a, 816b of the heating unit 120 (see Fig.11a). The frame 812 is attached to the carrier unit 110 by means of a clip housing 820 which includes a hold-down clip 822, the function of which will be described below.

[0127] Furthermore, a male contact 806 for the temperature sensor 480 is attached to a substantially Z-shaped lash element 824, which comprises a retaining arm 826. At the free distal end of the retaining arm 826, the temperature sensor 480 is arranged. At a small portion, a foil is provided, in particular a Kapton foil, which is electrically insulating and thermally conductive, as described in particular in European patent application 17188041.2.

[0128] exist Fig.11b On the left hand side of FIG. 8 , gap element 824 is shown mounted on frame 812, while Fig.11b On the right hand side, interstitial element 824 is shown separated.

[0129] When the clip housing 812 is mounted on the frame 812 and the gap member 824, pressing the clip 822 will contact the temperature sensor 480 and hold and push it toward the heating unit 120, such as Fig.11a A hold-down clip 822 may also be attached to the temperature sensor 480 to hold it in place.

[0130] To improve the contact performance, a contact paste 850 (eg, silver paste) having good thermal properties may optionally be used.

[0131] Furthermore, elastic elements 860 may optionally be used to compensate for installation tolerances (eg heat-resistant rubber, etc.).

[0132] Fig.11c There is now shown a second view of the frame 812, the interstitial element 824 and the clip housing 820. The interstitial element 824 is preferably formed from a Kapton foil as defined above.

[0133] In addition, Fig.11c , a ground contact 830 for the heating unit 120 is shown.

[0134] Fig.12 Also shown are three different mounting locations for the temperature sensor. A first mounting location 840 would be directly on the heating unit 120. This is the portion that is heated the most, so mounting of the temperature sensor may be difficult. A second location 842 is a location between the heating unit 120 and the carrier unit 110, which is closer to the carrier unit 110 and is therefore a preferred mounting location. Figures 11a to 11c In the present embodiment, a third placement 844 is used, which is easy to assemble and the temperature sensor 480 can be held in place by the clip housing 820.

[0135] Exemplary applications of the present invention generally involve situations where a fluid medium needs to be heated in an efficient manner, such as in household appliances such as dishwashers, clothes dryers and washing machines, small appliances such as coffee makers, irons, steam generators, etc., or in water heaters. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

[0136] In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality.

[0137] A single unit or device may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0138] The determination of the measured temperature, such as performed by one or more units or devices, may be performed by any other number of units or devices. For example, the measured temperature may be performed by a single temperature sensor or by any other number of different units. The determination and / or control of the heating system for heating the fluid medium may be implemented as program code means of a computer program and / or dedicated hardware.

[0139] The computer program may be stored / distributed on a suitable medium, such as an optical storage medium or a solid-state medium, provided together with or as a part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunications systems. The term "software code" may also refer to embedded software.

[0140] Any reference signs in the claims should not be construed as limiting the scope.

[0141] Reference numerals list

[0142] 1 Methods of controlling the heating system

[0143] 2 Receive the start signal

[0144] 3 Test routines

[0145] 4 Send a test signal

[0146] 6 Supply power to the heating unit

[0147] 8 Get the temperature test value

[0148] 10 Compare the obtained test values

[0149] 12 Determine if the test routine is successful

[0150] 14 Continue the boot process

[0151] 16 Entering a safe state

[0152] 30 Controller

[0153] 32 Memory

[0154] 34 Software Code

[0155] 36 processors

[0156] 40, 42, 44, 46 Graphs, heating curves

[0157] 100 Heating system components

[0158] 101 Wet Side

[0159] 102 Dry side

[0160] 110 carrier units

[0161] 111 Round hole

[0162] 112 Grooves

[0163] 113 Circumference

[0164] 120 Heating unit

[0165] 122 Thermal paste

[0166] 123 Heating unit connection pin

[0167] 140, 240, 340 heat conducting plate

[0168] 141, 241, 341 protruding parts

[0169] 142 Separation Part

[0170] 143 Groove

[0171] 144, 244 Non-separated part

[0172] 170, 180, 270, 370, 470, 480, 770 temperature sensors

[0173] 170a, 180a, 270a, 370a, 470a first temperature sensor

[0174] 170b, 180b, 270b, 370b, 470b Second temperature sensor

[0175] 181 Shielding Unit

[0176] 182 Hollow Room

[0177] 250a First Ceramic Pad

[0178] 250b Second Ceramic Pad

[0179] 260, 360, 760, 261, 361, 461 Insulation layer

[0180] 300, 600 plug

[0181] 301 Connection

[0182] 302, 602 Connecting pin

[0183] 345 Upper extension

[0184] 400 Undercut

[0185] 500 Thermoplastic Layer

[0186] 761 Conductor Path

[0187] 800 Pump Housing

[0188] 802 Connector Board

[0189] 804 First Male Connector

[0190] 806 Second male connector

[0191] 808 First female connector

[0192] 810 Second female connector

[0193] 812 Frame

[0194] 814a, 814b Contacts

[0195] 816a, 816b Contacts of the heating unit

[0196] 820 Clip Housing

[0197] 822 Press the clip

[0198] 826 Holding Arm

[0199] 824 Gap Element

[0200] 828 Foil Element

[0201] 830 Ground contact

[0202] 840 First installation position (hot zone - on heating element)

[0203] 842 Second installation position (mixed area - between 840 and 844)

[0204] 844 Third installation position (medium temperature area)

[0205] 850 Contact Paste

[0206] 860 Elastic Element

[0207] S1 Start signal

[0208] S2 test signal

[0209] S2R test return signal

[0210] S3 Power supply signal for heating unit

[0211] S4 Temperature test value signal

[0212] S5 feedback signal

[0213] Td Detection time

[0214] Te The temperature value that exceeds the threshold

[0215] Tf is the temperature below the threshold

[0216] Th Heating time

[0217] Tt temperature threshold

[0218] T0 Test start time

[0219] T1 test end time

[0220] T2 duration

[0221] Wt Test power level

[0222] Y Slope of the heating curve

Claims

1. A method (1) of controlling a heating system component (100) of a heating system for heating a fluid medium, The heating system component (100) comprises: A carrier unit (110); a heating unit (120) coupled to the carrier unit (110); as well as Controller; wherein the carrier unit (110) comprises a wet side and a dry side, wherein the wet side corresponds to a surface of the carrier unit (110) configured to contact the fluid medium, and wherein the dry side is located on a surface opposite to the wet side; and further comprising at least one temperature sensor (170a, 180a, 180b, 270, 370, 470), in particular an NTC thermistor, wherein the temperature sensor (170a, 180a, 180b, 270, 370, 470, 480) is effectively in thermal contact with at least a portion of the upper surface of the dry side of the carrier unit (110), The method (1) comprises: - receiving (2) a start signal (S1) at the controller (30) to start the heating system component (100); - performing a test routine (3) on at least one temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770); - If the test routine (3) is unsuccessful: entering a safe state (16) of the heating system component (100); The test routine includes: - supplying power (6, S3) to the heating unit (120) at a predetermined test power level (Pt) for a predetermined test period (Th); - obtaining (8) a temperature test value (S4) measured by the at least one temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770); - comparing (10) the obtained temperature test value (S4) with a predetermined temperature threshold value (Tt); The temperature test value (S4) is obtained after an additional delay time after the predetermined test time period (Th) ends.

2. The method of claim 1, wherein: The test routine includes: - sending (4) a test signal (S2) from the controller (30) to the at least one temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770).

3. The method of claim 1, wherein: The test power level (Pt) is 100% or less of the maximum power level, preferably 50% or less.

4. The method of claim 3, wherein: The test power is supplied in pulses.

5. The method of claim 1, wherein: A plurality of temperature test values ​​are obtained (S4), and the method further includes the following steps: - calculating a single heating curve (40, 42) based on the plurality of temperature test values ​​(S4), or calculating individual temperature curves for each temperature test value.

6. A method as claimed in any preceding claim, comprising: - providing the heating system component (100) with a second temperature sensor (170b, 180b, 270b, 370b, 470b), which is located distally of the first temperature sensor (170a, 180a, 270a, 370a, 470a), preferably close to the first temperature sensor (480, 770).

7. A method as claimed in any preceding claim, comprising: - providing a connection between the controller (30) and the at least one temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770) by means of a primary connection and providing a second temperature sensor by means of a redundant connection.

8. A method as claimed in any preceding claim, comprising: - The heating unit (120) is recessed into a groove (112) provided on the dry side of the carrier unit (110).

9. A heating system component (100) for a heating system for heating a fluid medium, The heating system component (100) comprises: A carrier unit (110); a heating unit (120) coupled to the carrier unit (110); as well as Controller; wherein the carrier unit (110) comprises a wet side and a dry side, wherein the wet side corresponds to a surface of the carrier unit (110) configured to contact the fluid medium, and wherein the dry side is located on a surface opposite to the wet side; and further comprising at least one temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770), in particular an NTC thermistor, wherein the temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770) is effectively in thermal contact with at least a portion of the upper surface of the dry side of the carrier unit (110), The controller (30) comprises a memory (32) and a processor (36), wherein the memory (32) comprises software code (34) which, when executed on the processor (36), enables the controller (30) to perform the method (1) according to any one of claims 1 to 8.

10. The heating system component (100) of claim 9, wherein: The heat conducting plate (140) comprises a portion thermally connected to the heating unit (120) and a portion thermally connected to the carrier unit (110), which is remote from the connection to the heating unit (120), providing a mixed temperature of the two temperature levels on the heat conducting plate (140), wherein the at least one temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770) is attached at a position (842, 844), ensuring the desired mixed temperature on one side and maintaining the temperature of the at least one temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770) within a specified operating temperature range of the at least one temperature sensor (170a, 180a, 270a, 370a, 460, 470a, 480, 770), which is significantly lower than the maximum temperature of the heating unit.

11. The heating system component (100) of claim 10, wherein: The heating unit (120) is recessed into a groove (112) provided on the dry side of the carrier unit (110).

12. The heating system component (100) of claim 11, wherein: The heating units are in the form of quartzite heaters, flow-through heaters, flat plate heaters, thick film and thin film heaters.

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