JP2009299985A - Heat pump type heating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump type heating device capable of accurately obtaining a refrigerant temperature in refrigerant piping without forming a separating part between the refrigerant piping and water piping in a water heat exchanger. <P>SOLUTION: In a heat exchanger of this heat pump type heating device, in which the refrigerant piping in which a refrigerant circulated in a heat pump cycle is circulated, and a heated fluid piping in which heated fluid heated by heat exchange with the refrigerant is circulated are spirally stacked while being thermally joined, a temperature of the refrigerant detected by a refrigerant temperature detecting means disposed while being externally kept into contact with the refrigerant piping, is corrected on the basis of, at least, a rotational frequency of a compressor. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat pump type heating device such as a heat pump type hot water heater provided with a heat exchanger that heats a fluid such as water or brine (antifreeze) by a refrigerant circulated in a heat pump cycle, and in particular, the refrigerant in the heat exchanger. The present invention relates to a technique for detecting the temperature of the refrigerant in the refrigerant pipe through which the refrigerant is circulated.

Conventionally, a heat pump that has a heat pump cycle connected to a compressor, an expansion valve, a water heat exchanger, an outdoor air heat exchanger, etc., and heats the water by heat exchange with the refrigerant circulated in the heat pump cycle. A hot water heater is known (see, for example, Patent Document 1). In the water heat exchanger, a refrigerant pipe through which the refrigerant circulated through the heat pump cycle and a water pipe through which water heated by heat exchange with the refrigerant circulates are spirally stacked.
Here, in the heat pump type water heater, as an index for controlling a compressor, an expansion valve, a fan of an outdoor air heat exchanger, etc. that form a heat pump cycle, the temperature of the refrigerant flowing through the water heat exchanger (condensation temperature) ) Must be detected.
Specifically, in the heat pump type water heater disclosed in Patent Document 1, a water heat exchanger having two coil bodies having the same shape in which a refrigerant pipe and a water pipe are laminated in a spiral shape is disclosed. In this water heat exchanger, the refrigerant pipe and the water pipe connecting the two coil bodies are separated, and a temperature sensor is installed in the separated refrigerant pipe to detect the refrigerant condensation temperature. Yes. In such a configuration, the condensation temperature of the refrigerant in the refrigerant pipe can be detected without being affected by the water in the water pipe.
Japanese Patent No. 3949589

However, in a configuration in which two coil bodies are formed and connected as in Patent Document 1, it is troublesome in the production process to connect the two coil bodies with a refrigerant pipe and a water pipe, which increases costs. There is a problem of being connected. Further, since it is necessary to separate the refrigerant pipe and the water pipe at the position where the temperature sensor is installed, heat exchange between the refrigerant and water cannot be performed at that portion.
For this reason, it is originally desirable to have a configuration that can detect the condensation temperature of the refrigerant without providing a separation portion between the refrigerant pipe and the water pipe. However, if a temperature sensor is provided on the refrigerant pipe at a location where the refrigerant pipe and the water pipe are in contact, the temperature detected by the temperature sensor is affected by the heat from the water in the water pipe, and the temperature of the refrigerant in the refrigerant pipe is reduced. There is a problem that it cannot be detected accurately.
Accordingly, the present invention has been made in view of the above circumstances, and an object of the present invention is to accurately set the refrigerant temperature in the refrigerant pipe without providing the refrigerant pipe and the separated portion of the water pipe in the water heat exchanger. An object of the present invention is to provide a heat pump type heating device that can be obtained.

In order to achieve the above object, the present invention is connected to a heat pump cycle having a compressor, an outdoor air heat exchanger and an expansion mechanism, and a refrigerant pipe through which a refrigerant circulated in the heat pump cycle flows, and heat of the refrigerant. It is applied to a heat pump type heating device provided with a heat exchanger stacked in a spiral shape so as to be thermally coupled to one or a plurality of heated fluid pipes through which the heated fluid heated by exchange flows. A refrigerant temperature detecting means for circumscribing the refrigerant pipe of the heat exchanger and detecting the temperature of the refrigerant in the refrigerant pipe; and at least the temperature of the refrigerant detected by the refrigerant temperature detecting means. It is comprised as a heat pump type heating apparatus characterized by including the refrigerant | coolant temperature correction | amendment means correct | amended based on the rotation speed of a machine. In order to detect the condensing temperature of the refrigerant as accurately as possible, it is desirable that the refrigerant temperature detecting means is provided at substantially the center of the pipe length of the refrigerant pipe in the heat exchanger.
In the heat pump type heating apparatus configured as described above, the temperature error can be excluded by correcting the refrigerant temperature detected by the refrigerant temperature detecting means based on the rotation speed of the compressor, and the temperature error can be eliminated with high accuracy. It is possible to acquire the refrigerant temperature in the refrigerant pipe. Therefore, in the heat pump type heating device, the structure of the heat exchanger can be simplified without providing a separation portion between the refrigerant pipe and the heated fluid pipe. Here, in the present invention, in the heat exchanger of the heat pump type heating device, the degree of the thermal influence that the temperature detected by the refrigerant temperature detecting means receives from the heated fluid piping greatly depends on the rotational speed of the compressor. This is realized by finding

By the way, in the heat pump type heating device, not only the rotation speed of the compressor but also the inflow temperature of the fluid into the heated fluid piping in the heat exchanger and the outflow of the fluid from the heated fluid piping in the heat exchanger. The temperature error of the refrigerant detected by the refrigerant temperature detecting means also varies depending on the temperature.
Therefore, the refrigerant temperature correcting means may be configured to correct the refrigerant temperature detected by the refrigerant temperature detecting means based on the rotation speed of the compressor and the inflow temperature or the outflow temperature. desirable. As a result, it is possible to cope with variations in temperature error due to changes in the inflow temperature and the outflow temperature, and the refrigerant temperature in the refrigerant pipe can be detected with higher accuracy.

As a method for correcting the detected temperature based on the rotational speed of the compressor, for example, the rotational speed of the compressor, the temperature detected by the refrigerant temperature detecting means, and the temperature error of the refrigerant temperature in the refrigerant pipe of the heat exchanger are calculated. Error correspondence information storage means for storing error correspondence information indicating a correspondence relationship is provided, and the refrigerant temperature correction means determines the refrigerant temperature detected by the refrigerant temperature detection means as the rotation speed of the compressor and the It is conceivable to make a correction based on the error correspondence information. This makes it possible to correct the detected temperature based on the rotation speed of the compressor.
Further, as a correction method when the refrigerant temperature correction means performs correction in consideration of the inflow temperature and the outflow temperature, the error correspondence information stored in the error correspondence information storage means is used as the inflow temperature. It is conceivable that the refrigerant temperature is changed according to the value of the outflow temperature and the refrigerant temperature detected by the refrigerant temperature detecting means is corrected based on the error correspondence information after the change and the rotation speed of the compressor. . Thereby, it is possible to correct the detected temperature based on the rotation speed of the compressor and the inflow temperature or the outflow temperature.
By the way, the refrigerant temperature corrected by the refrigerant temperature correction means is used for a compressor control means for performing drive control of the compressor based on the refrigerant temperature. Thus, the compressor control means can appropriately perform high-pressure control of the compressor based on the refrigerant condensation temperature with high accuracy after being corrected by the refrigerant temperature correction means.

  According to the present invention, the temperature error can be excluded by correcting the refrigerant temperature detected by the refrigerant temperature detection means based on the rotation speed of the compressor, and the refrigerant temperature in the refrigerant pipe can be accurately detected. Is possible to get. Therefore, in the heat pump type heating device, the structure of the heat exchanger can be simplified without providing a separation portion between the refrigerant pipe and the heated fluid pipe.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings so that the present invention can be understood. The following embodiment is an example embodying the present invention, and does not limit the technical scope of the present invention.
FIG. 1 is a block diagram showing a schematic configuration of a heat pump type hot water heater X according to an embodiment of the present invention, and FIG. 2 is a schematic external view of a water heat exchanger 14 provided in the heat pump type hot water heater X. 3 is a diagram for explaining a temperature sensor 31 provided in the water heat exchanger 14, and FIG. 4 is a diagram for explaining an example of error correspondence information.
First, the schematic configuration of the heat pump type hot water heater X according to the embodiment of the present invention will be described with reference to FIG. In the present embodiment, as an example of the heat pump type heating device according to the present invention, a heat pump type hot water heater X that supplies hot water will be described as an example. However, the present invention uses, for example, hot water or brine (antifreeze). It can be applied to a heat pump floor heating device that uses floor heating, a reheating device that boils water in a bathtub, and a system that has these functions.

As shown in FIG. 1, the heat pump hot water supply X includes a heat pump cycle (refrigeration cycle) 1 in which refrigerant is circulated, a hot water supply circuit 2 for storing or supplying hot water, and the temperature of the refrigerant or water at each arrangement position. Temperature sensors 31 to 33, and a control unit 4 that comprehensively controls the heat pump type water heater X. Here, as the refrigerant circulated in the heat pump cycle 1, for example, a carbon dioxide refrigerant such as CO ₂ refrigerant (a kind of natural refrigerant) or an HFC refrigerant such as R410A is used.
The heat pump cycle 1 includes a compressor 11 that compresses refrigerant, a water heat exchanger 14 that performs heat exchange between the refrigerant flowing out of the compressor 11 and water in the hot water supply circuit 2 (an example of a fluid to be heated) (heat exchange). One example), an expansion valve 13 that changes (expands) the refrigerant flowing out of the water heat exchanger 14, and an outdoor air heat exchanger 12 that exchanges heat between the refrigerant and outdoor air. . The expansion valve 13 is merely an example of an expansion mechanism that changes the state of the refrigerant, and another expansion mechanism such as a capillary tube may be employed.
The temperature sensor 31 (an example of the refrigerant temperature detection means) is used to detect the condensation temperature of the refrigerant in the heat pump cycle 1 and is disposed in the water heat exchanger 14. The temperature detected by the temperature sensor 31 is input to the control unit 4. The temperature detection by the temperature sensor 31 will be described in detail later.

On the other hand, the hot water supply circuit 2 includes a hot water storage tank 21 for storing hot water (for example, about 45 to 90 ° C.) heated by heat exchange with the refrigerant in the water heat exchanger 14, and water from a lower layer of the hot water storage tank 21. A circulation pump 22 for circulating water to the upper layer of the hot water storage tank 21 through the heat exchanger 14, water from the water supply port 23 and hot water supplied from the upper layer of the hot water storage tank 21 are mixed to supply hot water from the hot water supply port 24. And an electromagnetic three-way valve 25 for adjusting the temperature of the hot water to be used.
The temperature sensor 32 is an outflow temperature of warm water from the water heat exchanger 14 (hereinafter referred to as “hot water temperature”), and the temperature sensor 33 is an inflow temperature of water to the water heat exchanger 14 (hereinafter referred to as “water temperature”). The temperature sensor 34 detects the outside air temperature, and inputs the detection result to the control unit 4. The temperature sensor 32, the temperature sensor 33, and the temperature sensor 34 are a thermocouple, a thermistor, etc., and these are the same as those of a general heat pump type hot water heater. The temperature sensor 34 is disposed on the air suction side of the outdoor air heat exchanger 12.

The control unit 4 includes control devices such as a CPU, a RAM, and a ROM, and the CPU executes various processes in accordance with a control program stored in the ROM, so that each component of the heat pump type water heater X is performed. To control the operation. For example, the control unit 4 determines the rotation speed of the compressor 11 (hereinafter referred to as “comp rotation speed”) or the outdoor air heat exchanger 12 based on the incoming water temperature or the outside air temperature detected by the temperature sensors 33 and 34. The heating capacity of the heat pump cycle 1 is adjusted by controlling the rotational speed of the blower fan. Specifically, in the heat pump type water heater X, setting conditions for setting the compressor rotation speed according to the outside air temperature, the incoming water temperature, the target hot water temperature, and the like are stored in advance in the ROM or the like of the control unit 4. Controls the rotational speed of the compressor according to the set conditions.
Moreover, the control part 4 adjusts the water flow volume (hot-water supply amount) distribute | circulating the hot-water supply circuit 2 by controlling the drive of the circulation pump 22, and controls the hot water temperature to target hot-water temperature. For example, the control unit 4 performs PID control (P (proportional control), I (integral control), D (differential control), which performs feedback control based on three factors of deviation between the target hot water temperature and the hot water temperature, its integration, and its differentiation. )) And the like to change the pump flow rate of the circulation pump 22 and adjust the water flow rate, thereby controlling the tapping temperature to the target tapping temperature.
In addition, the relationship between the rotational speed of the compressor in the heat pump type hot water heater X and the water flow rate (or the rotational speed of the pump) of the circulation pump 22 is set as shown in Table 1 below. Based on the set condition of 1, it is also conceivable to configure the compressor rotational speed [rpm] to be changed according to the required water flow rate [l / min].

Here, the structure of the water heat exchanger 14 is demonstrated using FIG.2 and FIG.3.
As shown in FIG. 2, the water heat exchanger 14 includes a refrigerant pipe 141 through which the refrigerant of the heat pump cycle 1 flows, and a water pipe 142 (heated fluid pipe) through which water (an example of a heated fluid) flows from the hot water supply circuit 2. Example). The refrigerant pipe 141 and the water pipe 142 are formed in a spiral shape (coil shape, spiral shape, etc.) so as to be alternately stacked. For example, the water heat exchanger 14 is formed in a substantially rectangular shape, a substantially circular shape, a substantially flat shape, a substantially track shape, etc. in a plan view, and the expression “spiral shape” is a concept including a state wound in these shapes. is there. Here, in the water heat exchanger 14, the refrigerant pipe 141 and the water pipe 142 are in contact with each other over the entire length, and no separation portion is provided.
And the refrigerant | coolant piping 141 and the water piping 142 are brazed and the thermal connection is carried out (refer Fig.3 (a)). As a result, in the heat pump type water heater X, the refrigerant is circulated through the refrigerant pipe 141 of the water heat exchanger 14 and the water is circulated through the water pipe 142, whereby heat is exchanged between the refrigerant and water. Water is heated. At this time, the refrigerant in the refrigerant pipe 141 is condensed and liquefied by heat exchange with water in the water pipe 142.
In the present embodiment, since the heat pump type hot water heater X is described as an example, the water heat exchanger 14 performs heat exchange between water and the refrigerant. When applied to a heat pump type floor heating apparatus using an antifreeze liquid, the brine is heated by heat exchange with the refrigerant. Furthermore, when the heat pump type water heater X has functions such as a floor heating function and a bathtub reheating function in addition to the hot water supply function, a plurality of pipes (heated fluid pipes) are thermally connected to the refrigerant pipe 141. However, the present invention is also applicable to this case.

As described above, in the heat pump type hot water heater X, it is necessary to detect the temperature of the refrigerant flowing through the refrigerant pipe 141 of the water heat exchanger 14 in order to control the rotational speed of the compressor 11 of the compressor 11 in the heat pump cycle 1.
Therefore, a temperature sensor 31 that detects the refrigerant temperature in the refrigerant pipe 141 is provided at a substantially central portion of the pipe length of the refrigerant pipe 141 in the water heat exchanger 14. The temperature sensor 31 may be disposed at a position shifted from the central portion as long as the temperature sensor 31 can detect a temperature equivalent to the central portion of the pipe length of the refrigerant pipe 141.
Here, FIG. 3A is a diagram showing the main part of the cross section taken along the line AA in FIG. 2, and FIG. 3B is a diagram showing the structure of the temperature sensor 31.
As shown in FIG. 3B, the temperature sensor 31 uses a thermocouple 311 accommodated in a heat transfer tube 312. As shown in FIG. 3A, the temperature sensor 31 is brazed in a state of being circumscribed to the refrigerant pipe 141 so that the heat transfer pipe 312 is in close contact with the outer periphery of the refrigerant pipe 141, and heat is applied to the refrigerant pipe 141. Combined. The temperature sensor 31 may be a temperature sensor such as a thermistor.
In the water heat exchanger 14 configured as described above, the temperature sensor 31 is provided at the contact portion between the refrigerant pipe 141 and the water pipe 142, and thus the temperature of the refrigerant in the refrigerant pipe 141 detected by the temperature sensor 31. Is affected by heat from the water in the water pipe 142.
Therefore, in the heat pump type water heater X, a process for correcting the refrigerant temperature detected by the temperature sensor 31 is executed by the control unit 4. This will be specifically described below.

Hereinafter, the detected temperature correction process executed by the control unit 4 in the heat pump type hot water heater X will be described.
FIG. 4 shows the relationship between the rotational speed of the compressor in the heat pump type water heater X, the temperature detected by the temperature sensor 31, and the temperature difference between the detected temperature and the actual refrigerant temperature (hereinafter referred to as “temperature error”). . FIG. 4 shows the experimental results when the rotational speed of the compressor is changed under the conditions that the outside air temperature DB / WB (dry bulb temperature / wet bulb temperature) is 16/12 ° C., the incoming water temperature is 35 ° C., and the outgoing hot water temperature is 60 ° C. It is.
Referring to FIG. 4, it can be seen that the temperature error of the temperature detected by the temperature sensor 31 varies depending on the rotational speed of the compressor. Therefore, for example, the detected temperature cannot be accurately corrected only by adding a predetermined value to the detected temperature of the temperature sensor 31. Specifically, when the compressor speed is 1800 [rpm], the temperature detected by the temperature sensor 31 is 54.3 ° C., the actual refrigerant temperature is 56.8 ° C., and the temperature error is 2.5 ° C. When the compressor speed is 6000 [rpm], the temperature detected by the temperature sensor 31 is 51.8 ° C., the actual refrigerant temperature is 60.0 ° C., and the temperature error is 8.2 ° C.

Therefore, in the heat pump type water heater X, error correspondence information indicating the correspondence relationship between the compressor rotation speed and the temperature error (see FIG. 4) is stored in advance in the ROM of the control unit 4 (corresponding to error correspondence information storage means). The control unit 4 is configured to correct the temperature detected by the temperature sensor 31 based on the error correspondence information and the compressor rotation speed. Here, the control unit 4 when executing such correction processing corresponds to the refrigerant temperature correction means.
Specifically, if the compression speed is 1800 [rpm], the control unit 4 adds a temperature error of 2.5 ° C. corresponding to the compression speed to the temperature detected by the temperature sensor 31, and the compression speed is 6000. If it is [rpm], the detected temperature is corrected to the correct refrigerant temperature by adding a temperature error of 8.2 ° C. corresponding to the rotational speed of the compressor to the temperature detected by the temperature sensor 31. The control unit 4 acquires the compressor rotation speed of the compressor 11 based on, for example, the setting contents of the control instruction to the compressor 11 or based on the response signal from the compressor 11.
As described above, in the heat pump type water heater X, the temperature detected by the temperature sensor 31 arranged in contact with the refrigerant pipe 141 at the contact portion between the refrigerant pipe 141 and the water pipe 142 in the water heat exchanger 14 is based on the compression speed. It is possible to obtain the correct condensing temperature. Therefore, it is not necessary to provide a separation portion for separating the refrigerant pipe 141 and the water pipe 142 in the water heat exchanger 14, and the burden on the manufacturing process of the water heat exchanger 14 can be reduced and the cost can be reduced.
In the heat pump type hot water heater X, the controller 4 controls the compressor rotation speed of the compressor 11 provided on the heat pump cycle 1, the opening / closing degree of the expansion valve 13, and the outdoor air heat exchange by the control unit 4 based on the corrected refrigerant temperature. The fan rotation speed of the compressor 12 can be appropriately controlled, and for example, high-pressure control for preventing occurrence of a high-pressure abnormality of the compressor 11 can be executed with high accuracy. In addition, the control part 4 when performing drive control of the compressor 11 based on the refrigerant | coolant temperature after correction | amendment corresponds to a compressor control means.

In the present embodiment, the error correspondence information indicating the temperature error corresponding to the six stages of the rotational speed of the compressor as shown in FIG. 4 has been described. However, in the heat pump type water heater X, other rotational speeds are set. It may be possible.
Therefore, it is desirable that the control unit 4 is configured to perform correction using a relational expression determined based on the relationship between the rotational speed of the compressor and the temperature error obtained from the experimental result as shown in FIG. It is conceivable that the relational expression is stored in advance in the ROM of the control unit 4 as error correspondence information, or obtained by calculation in the control unit 4 each time.
Thereby, it is possible to perform correction corresponding to an arbitrary compression speed without storing a large amount of data in the ROM of the control unit 4. Of course, this does not exclude the configuration in which the data table having higher resolution than the error correspondence information shown in FIG. 4 is stored in the ROM of the control unit 4.

By the way, in the said embodiment, the case where the detection temperature by the temperature sensor 31 was correct | amended based on the compression rotation speed of the compressor 11 was mentioned as an example, and was demonstrated. On the other hand, in the heat pump type water heater X, the temperature error of the temperature detected by the temperature sensor 31 also varies depending on the incoming water temperature and the outgoing hot water temperature of the water heat exchanger 14.
Here, FIG. 5 shows the relationship between the rotational speed of the compressor and the temperature error when the incoming water temperature of the water heat exchanger 14 is different in the heat pump type water heater X, and FIG. 6 shows the water heat exchanger 14 in the heat pump type water heater X. The relationship between the compressor rotation speed and temperature error when the tapping temperature is different is shown.
Specifically, FIG. 5 shows that in the heat pump type water heater X, the incoming water temperature is 5 ° C., 17 ° C. under the condition that the outside air temperature DB / WB (dry bulb temperature / wet bulb temperature) is 16/12 ° C. and the tapping temperature 45 ° C. The relationship between the rotational speed of the compressor and the temperature error is shown for each ° C.
FIG. 6 shows that in the heat pump type water heater X, the outside air temperature DB / WB (dry bulb temperature / wet bulb temperature) is 16/12 ° C., the incoming water temperature is 17 ° C., and the hot water temperature is 45 ° C. and 60 ° C. The relationship between the rotational speed of the compressor and the temperature error in each case is shown.
As shown in FIGS. 5 and 6, in the heat pump type water heater X, the magnitude of the temperature error corresponding to the compressor rotation speed varies depending on the incoming water temperature and the outgoing hot water temperature of the water heat exchanger 14.

Therefore, in the heat pump type water heater X, when the temperature detected by the temperature sensor 31 is corrected by the control unit 4 based on the rotational speed of the compressor, a change in temperature error due to the incoming water temperature and the outgoing water temperature of the water heat exchanger 14 is also taken into consideration. It is desirable to do. That is, it is desirable that the control unit 4 corrects the temperature detected by the temperature sensor 31 based on the compressor rotation speed and the incoming water temperature or the outgoing water temperature.
For example, a plurality of data tables (for example, see the graph in FIG. 5, an example of error correspondence information) indicating the correspondence between the compressor rotation speed and the temperature error are previously provided in correspondence with each water temperature value of the water heat exchanger 14. It is conceivable that the data table is set and stored in a ROM or the like of the control unit 4 (corresponding to error correspondence information storage means). In this case, the control unit 4 extracts a data table corresponding to the incoming water temperature detected by the temperature sensor 33, and uses the temperature error corresponding to the compressor rotation speed determined in the data table, so that the temperature sensor 31 The detected temperature can be appropriately corrected. That is, the control unit 4 changes the data table used in accordance with the incoming water temperature, and performs correction based on the changed data table and the compressor rotation speed.
Further, if a predetermined relationship is established between the change in the incoming water temperature and the change in the temperature error, a plurality of data tables corresponding to the incoming water temperature are not prepared, but depending on the relationship, each time. It is desirable that the degree of correction of the temperature error with respect to the rotational speed of the compressor in the data table is changed. For example, if it is known that the temperature error changes by ± 0.1 ° C. when the incoming water temperature changes by ± 1 ° C. when the compressor speed is the same, the relational expression is stored. It is possible to make an appropriate correction that takes into account changes in the incoming water temperature.

The same applies to the tapping temperature of the water heat exchanger 14. That is, a plurality of data tables (for example, see the graph in FIG. 6, an example of error correspondence information) indicating the correspondence relationship between the compressor rotation speed and the temperature error in advance corresponding to each tapping temperature value of the water heat exchanger 14. It is conceivable to set the data table and store the data table in the ROM of the control unit 4 (corresponding to the error correspondence information storage means). Thereby, the control part 4 changes the data table used according to the tapping temperature, and uses the temperature error corresponding to the rotational speed of the compressor determined in the changed data table, so that the temperature detected by the temperature sensor 31 is changed. It can be corrected appropriately. Of course, if a predetermined relationship is established between the change in tapping temperature and the change in temperature error, the degree of correction of the temperature error may be changed each time depending on the relationship.
Furthermore, a temperature sensor such as performing correction based on both the rotational speed of the compressor and the incoming water temperature and the outgoing hot water temperature of the water heat exchanger 14, and correcting based on the temperature difference between the incoming water temperature and the outgoing hot water temperature. If correction is performed using more factors that affect the temperature error of the detected temperature by 31, the refrigerant condensing temperature can be detected with higher accuracy. In this case, for example, a relational expression (an example of error correspondence information) that can calculate a temperature error by substituting values of the compressor rotation speed, the incoming water temperature, and the outgoing hot water temperature may be defined in advance.

The block diagram which shows schematic structure of the heat pump type water heater which concerns on embodiment of this invention. The external appearance schematic diagram of the water heat exchanger provided in the heat pump type water heater which concerns on embodiment of this invention. The figure for demonstrating the temperature sensor provided in the water heat exchanger provided in the heat pump type hot water heater which concerns on embodiment of this invention. The figure for demonstrating an example of error corresponding | compatible information. The figure which shows the relationship between the compression rotation speed and temperature error in case the incoming temperature of a water heat exchanger differs in a heat pump type water heater. The figure which shows the relationship between the compression rotation speed and temperature error when the tapping temperature of a water heat exchanger differs in a heat pump type water heater.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Heat pump cycle 11 ... Compressor 12 ... Outdoor air heat exchanger 13 ... Expansion valve 14 ... Water heat exchanger (an example of a heat exchanger)
141 ... Refrigerant piping 142 ... Water piping (an example of heated fluid piping)
2 ... Hot water supply circuit 21 ... Hot water storage tank 22 ... Circulation pump 23 ... Water supply port 24 ... Hot water supply port 25 ... Electromagnetic three-way valve 31 ... Temperature sensor (an example of refrigerant temperature detection means)
32, 33, 34 ... temperature sensor 4 ... control unit X ... heat pump type hot water heater (an example of a heat pump type heating device)

Claims (6)

Connected to a heat pump cycle having a compressor, an outdoor air heat exchanger and an expansion mechanism, a refrigerant pipe through which the refrigerant circulated in the heat pump cycle flows, and a heated fluid heated by heat exchange with the refrigerant circulates A heat pump type heating device including a heat exchanger stacked in a spiral shape so as to be thermally coupled to one or a plurality of heated fluid pipes,
A refrigerant temperature detecting means provided externally to the refrigerant pipe of the heat exchanger and detecting the temperature of the refrigerant in the refrigerant pipe;
Refrigerant temperature correction means for correcting the temperature of the refrigerant detected by the refrigerant temperature detection means based on at least the rotational speed of the compressor;
A heat pump type heating device comprising:   The refrigerant temperature correction means is configured to adjust the rotational speed of the compressor and the inflow temperature of the fluid to the heated fluid pipe in the heat exchanger and / or the outflow temperature of the fluid from the heated fluid pipe in the heat exchanger. The heat pump heating device according to claim 1, wherein the temperature of the refrigerant detected by the refrigerant temperature detecting means is corrected based on the temperature. Error correspondence information storage means for storing error correspondence information indicating a correspondence relationship between the rotational speed of the compressor, the temperature detected by the refrigerant temperature detection means, and the temperature error of the refrigerant temperature in the refrigerant pipe of the heat exchanger. Prepared,
2. The heat pump heating according to claim 1, wherein the refrigerant temperature correcting means corrects the refrigerant temperature detected by the refrigerant temperature detecting means based on the rotation speed of the compressor and the error correspondence information. apparatus. Error correspondence information storage means for storing error correspondence information indicating a correspondence relationship between the rotational speed of the compressor, the temperature detected by the refrigerant temperature detection means, and the temperature error of the refrigerant temperature in the refrigerant pipe of the heat exchanger. Prepared,
The refrigerant temperature correction means changes the error correspondence information stored in the error correspondence information storage means according to the value of the inflow temperature and / or the outflow temperature, and the error correspondence information after the change and the compressor The heat pump heating device according to claim 2, wherein the temperature of the refrigerant detected by the refrigerant temperature detecting means is corrected based on the rotation speed of the refrigerant.   The heat pump heating device according to any one of claims 1 to 4, further comprising compressor control means for performing drive control of the compressor based on the refrigerant temperature corrected by the refrigerant temperature correction means.   The heat pump heating device according to any one of claims 1 to 5, wherein the refrigerant temperature detection means is provided at a substantially central part of a pipe length of a refrigerant pipe in the heat exchanger.

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