JP6013738B2 - Heating system - Google Patents

Description

  The present invention relates to a heating device. In particular, the present invention relates to a heating apparatus that uses a heat pump that absorbs heat from the atmosphere as a heat source.

  Patent Document 1 discloses a heating device that uses a heat pump that absorbs heat from the atmosphere as a heat source. This heating device includes a tank that stores a heat medium, a heat pump that heats the heat medium, and a heating terminal that heats the heat medium by releasing heat. The tank and the heat pump are connected by a heat storage circulation path for circulating the heat medium, and the tank and the heating terminal are connected by a heating circulation path for circulating the heat medium.

JP 2003-240341 A

  When heating is performed at the heating terminal while driving the heat pump, it is preferable to balance the heat radiation amount at the heating terminal and the heat amount at the heat pump from the viewpoint of preventing heat loss at the tank. In a heat pump that uses carbon dioxide as a refrigerant, the heating capacity cannot be changed continuously, and the heating capacity is switched in stages. However, the heat radiation amount in the heating terminal continuously varies depending on the heating situation. For this reason, when it is going to control a heat pump according to the heat radiation amount in a heating terminal, it will be necessary to frequently perform on / off of a heat pump and switching of a heating capability. If the heat pump is started and stopped and the heating capacity is frequently switched, the deterioration of the parts constituting the heat pump is accelerated.

  The present specification provides a technique for solving the above problems. In this specification, in the heating apparatus using a heat pump that absorbs heat from the atmosphere as a heat source, there is provided a technique capable of suppressing the number of times the heat pump starts and stops and the heating capacity is switched.

The heating device disclosed in this specification includes a heat pump that absorbs heat from the atmosphere and heats the heat medium, a tank that stores the heat medium, a heat storage circuit that circulates the heat medium between the heat pump and the tank, and heat dissipation from the heat medium. A heating terminal for heating, a heat radiation circuit for circulating the heating medium between the heating terminal and the tank, an upper tank thermistor for detecting the temperature of the heating medium stored in the upper part of the tank, and an intermediate part of the tank A middle tank thermistor for detecting the temperature of the stored heat medium and a lower tank thermistor for detecting the temperature of the heat medium stored in the lower part of the tank are provided. In the heating device, the heating capacity of the heat pump can be switched in stages to at least one of the first stage, the second stage stronger than the first stage, and the third stage stronger than the second stage. In the heating device, when the heating terminal performs heating without stopping the heat pump, when the heating capacity of the heat pump is in the first stage or the second stage, the detected temperature of the upper tank thermistor is the first predetermined temperature. When the temperature is equal to or lower than the temperature, or when the temperature detected by the middle tank thermistor is equal to or lower than the second predetermined temperature lower than the first predetermined temperature, the heating capacity of the heat pump is switched to the third stage, and the heating capacity of the heat pump is When the detected temperature of the upper tank thermistor exceeds a third predetermined temperature higher than the first predetermined temperature and the detected temperature of the middle tank thermistor exceeds a fourth predetermined temperature higher than the second predetermined temperature, the heat pump is heated. The capacity is switched to the second stage, and when the heating capacity of the heat pump is the second stage or the third stage, the middle tank thermistor is detected. When the temperature exceeds the fifth predetermined temperature and the detected temperature of the lower tank thermistor exceeds the sixth predetermined temperature lower than the fifth predetermined temperature, the heating capacity of the heat pump is switched to the first stage, and the heating capacity of the heat pump is When the detected temperature of the middle tank thermistor is equal to or lower than a seventh predetermined temperature lower than the fifth predetermined temperature or when the detected temperature of the lower tank thermistor is equal to or lower than an eighth predetermined temperature lower than the sixth predetermined temperature in one stage In addition, the heating capacity of the heat pump is switched to the second stage. Here, the fourth predetermined temperature and the sixth predetermined temperature are higher than the second predetermined temperature and the eighth predetermined temperature, the first predetermined temperature and the seventh predetermined temperature are higher than the fourth predetermined temperature and the sixth predetermined temperature, The 3 predetermined temperature and the 5th predetermined temperature are higher than the 1st predetermined temperature and the 7th predetermined temperature.

In the above heating device, when heating is performed at the heating terminal while driving the heat pump, based on the detected temperature of the upper tank thermistor, the detected temperature of the middle tank thermistor, the detected temperature of the lower tank thermistor and the current heating capacity of the heat pump. Switch the heating capacity of the heat pump. As described above, in a heating apparatus in which a tank is interposed between a heating terminal and a heat pump, the tank plays a role in buffering fluctuations in the amount of heat released from the heating terminal. There is no need to switch abilities immediately. Therefore, based on the detected temperature of the upper tank thermistor, the detected temperature of the middle tank thermistor, the detected temperature of the lower tank thermistor and the current heating capacity of the heat pump, the heating capacity of the heat pump is switched according to the heat storage state of the tank. Thus, the heat radiation amount in the heating terminal and the heating amount in the heat pump can be balanced over a long period of time without frequently switching on and off the heat pump and switching the heating capacity. By setting it as such a structure, the frequency | count of the start / stop of a heat pump and the switching of a heating capability can be suppressed.

Another heating device disclosed in this specification includes a heat pump that absorbs heat from the atmosphere and heats the heat medium, a tank that stores the heat medium, a heat storage circuit that circulates the heat medium between the heat pump and the tank, and a heat medium. A heating terminal that radiates heat from the heating terminal, a heat radiation circuit that circulates the heating medium between the heating terminal and the tank, an upper tank thermistor that detects the temperature of the heating medium stored in the upper part of the tank, and the middle of the tank The middle tank thermistor that detects the temperature of the heat medium stored in the section, the lower tank thermistor that detects the temperature of the heat medium stored in the lower part of the tank, and the temperature of the heat medium flowing from the tank to the heat pump in the heat storage circuit A heat storage forward thermistor to detect and a heat storage return thermistor to detect the temperature of the heat medium flowing from the heat pump to the tank in the heat storage circuit are provided. In the heating device, the heating capacity of the heat pump can be switched in stages to at least one of the first stage, the second stage stronger than the first stage, and the third stage stronger than the second stage. In the heating device, when heating is performed at the heating terminal while continuing to drive without stopping the heat pump, when the heating capacity of the heat pump is the first stage or the second stage, the heat storage amount of the tank is equal to or less than the first predetermined value. When the heating capacity of the heat pump exceeds the second predetermined value higher than the first predetermined value when the heating capacity of the heat pump is in the third stage and the heat storage amount of the tank exceeds the second predetermined value, the heat pump When the heat storage capacity of the tank exceeds the third predetermined value higher than the second predetermined value when the heating capacity of the heat pump is in the second stage or the third stage, When the capacity is switched to the first stage and the heating capacity of the heat pump is at the first stage, the amount of heat stored in the tank is lower than the third predetermined value and lower than the fourth predetermined value, which is higher than the second predetermined value. To switch the heating capacity of the heat pump in the second stage. In that heating system, the amount of heat stored in the tank is calculated by multiplying the tank capacity by the difference between the average detected temperature of the upper tank thermistor, middle tank thermistor, lower tank thermistor and heat storage return thermistor and the detected temperature of the heat storage forward thermistor. Alternatively, it is calculated by multiplying the difference between the average detected temperature of the upper tank thermistor, the middle tank thermistor and the lower tank thermistor and the detected temperature of the heat storage thermistor by the capacity of the tank.

  According to the above heating device, when the amount of heat stored in the tank is likely to decrease and the hot water is likely to run out, the heating capacity of the heat pump is increased, and the amount of heat stored in the tank is likely to increase to become fully stored By reducing the heating capacity of the heat pump, the tank can be prevented from running out of hot water or being fully stored. The tank can always be responsible for buffering fluctuations in the amount of heat released from the heating terminal.

It is a figure which shows typically the structure of the hot-water supply heating system 10 ( reference hot-water supply heating system 100 of an Example ) of a reference example . It is a figure which shows the flow of a heat medium when heating, operating the heat pump unit. It is a figure which shows the flow of a heating medium in case the temperature of the heating medium sent from the tank 30 to the heating outbound path 56 is high with respect to the temperature of the heating medium which the heating terminal 90 requires. It is a figure which shows the flow of a heating medium in case the temperature of the heating medium sent from the tank 30 to the heating outbound path 56 is low with respect to the temperature of the heating medium which the heating terminal 90 requires.

  In one embodiment of the present invention, it is preferable to use water or antifreeze as the heating medium.

  In one embodiment of the present invention, carbon dioxide is preferably used as the refrigerant used in the heat pump.

(Reference example)
Reference examples of the present invention will be described with reference to the drawings. FIG. 1 shows a hot water supply / heating system 10 of a reference example . As shown in FIG. 1, the hot water supply and heating system 10 includes a heat pump unit 20, a tank unit 28, a hot water supply and heating unit 80, and a heating terminal 90.

The heat pump unit 20 is a heat pump that absorbs heat from the atmosphere and heats the heat medium sent from the tank unit 28. Although not shown, the heat pump unit 20 includes a compressor, a radiator, an expansion valve, an evaporator, and a refrigerant circulation path that connects them in order. In addition, a fan that blows air to the evaporator, a motor that drives the fan, and the like are also provided. The refrigerant circulation path is filled with carbon dioxide, which is a refrigerant. Since the details of the heat pump unit 20 are the same as known ones, the description thereof is omitted here. The heat pump unit 20 can switch the heating capacity in stages. In this reference example , the heat pump unit 20 can switch the heating capacity in three stages of “small”, “medium”, and “large” in the order of weakness. The heat pump unit 20 is provided with a circulation pump 22 that circulates the heat medium between the heat pump unit 20 and the tank unit 28.

The tank unit 28 includes a tank 30 that stores a heat medium. The heat medium of this reference example is antifreeze. The tank 30 of this reference example is an example, but has a capacity of 30 liters. The tank 30 is provided with an upper tank thermistor 42a, a middle tank thermistor 42b, and a lower tank thermistor 42c. The upper tank thermistor 42a is provided in the upper part of the tank 30 (for example, 10 liters from the top of the tank 30), and the middle tank thermistor 42b is in the middle of the tank 30 (for example, 15 liters from the top of the tank 30). The lower tank thermistor 42c is provided in the lower part of the tank 30 (for example, 20 liters from the top of the tank 30). The upper tank thermistor 42 a, the middle tank thermistor 42 b, and the lower tank thermistor 42 c are connected to the controller 54 of the tank unit 28. Note that the thermistors that detect the temperature of the heat medium in the tank 30 are not limited to the above three, and may be provided two or four or more.

The tank 30 is connected to the heat pump unit 20 via a heat storage forward path 34 and a heat storage return path 32. The heat storage forward path 34 is a pipe line that sends a heat medium from the tank 30 to the heat pump unit 20, and is connected to the bottom of the tank 30. The heat storage return path 32 is a pipe line that returns the heat medium from the heat pump unit 20 to the tank 30, and is connected to the top of the tank 30. The heat storage outward path 34 and the heat storage return path 32 constitute a circulation path for circulating the heat medium between the heat pump unit 20 and the tank 30. The circulation pump 22 described above is provided in the circulation path. Although the circulation pump 22 of this reference example is built in the heat pump unit 20, the position of the circulation pump 22 is not particularly limited.

  A manual valve 24 and a heat storage outward thermistor 44 are provided in the heat storage outward path 34. Similarly, the heat storage return path 32 is also provided with a manual valve 24 and a heat storage return path thermistor 46. The heat storage outward thermistor 44 and the heat storage return thermistor 46 are connected to the controller 54 of the tank unit 28. The controller 54 grasps the temperature of the heat medium before heating by the heat pump unit 20 from the temperature detected by the heat storage forward path thermistor 44, and grasps the temperature of the heat medium after heating by the heat pump unit 20 from the temperature detected by the heat storage return path thermistor 46. can do.

  The heating terminal 90 performs heating by dissipating heat from the tank 30. The heating terminal 90 is, for example, a panel heater, a panel radiator, floor heating, a fan convector, or a hot water room air conditioner. The heating terminal 90 is connected to the tank 30 via the heating forward path 56 and the heating return path 60. The heating forward path 56 is a pipe line that sends a heat medium from the tank 30 to the heating terminal 90, and is connected to the top of the tank 30. The heating return path 60 is a conduit that returns the heat medium from the heating terminal 90 to the tank 30, and is connected to the bottom of the tank 30. The heating forward path 56 and the heating return path 60 constitute a circulation path for circulating the heat medium between the tank 30 and the heating terminal 90.

A drain pipe 50 having a manual valve 52 is connected to the heating return path 60. An expansion tank 70 is provided in the heating return path 60. In this reference example , since the circuit through which the heat medium circulates is a sealed circuit, an expansion tank 70 is prepared to absorb the thermal expansion of the heat medium. The position where the expansion tank 70 is connected is not limited to the heating return path 60, and may be connected to the heating outbound path 56 or another path, for example.

  The heating forward path 56 is connected to the heating terminal 90 via the hot water supply / heating unit 80. The hot water supply / heating unit 80 is a combustion-type heat source machine, and includes two burners 84 and 86 that combust combustible gas. One burner 84 is for hot water supply and heats the clean water flowing through the hot water supply pipe line 82. The other burner 86 is for heating, and heats the heat medium flowing through the heating forward path 56 as necessary. The hot water supply / heating unit 80 has a controller 88. Further, the hot water supply / heating unit 80 is provided with a circulation pump 87 for circulating a heat medium between the heating terminal 90 and the tank unit 28. The position where the circulation pump 87 is provided is not limited to the hot water supply / heating unit 80 and is not particularly limited. According to this configuration, when the temperature of the heating medium sent to the heating terminal 90 through the heating outbound path 56 is too low, the heating medium flowing through the heating outbound path 56 is heated by the burner 86 to be sent to the heating terminal 90. The temperature of the heat medium to be produced can be raised.

  The heating forward path 56 and the heating return path 60 are connected via a bypass path 64. Thereby, a part or all of the heat medium flowing in the heating return path 60 can be sent to the heating outbound path 56 without passing through the tank 30. In addition, a mixing valve 66 is provided at a branch position between the heating return path 60 and the bypass path 64, and the flow rate of the heating medium sent from the heating return path 60 to the heating outbound path 56 via the bypass path 64, and heating The ratio of the flow rate of the heat medium sent from the return path 60 to the heating forward path 56 via the tank 30 can be adjusted. The mixing valve 66 is connected to the controller 54, and its operation is controlled by the controller 54. According to this configuration, when the temperature of the heat medium sent to the heating terminal 90 through the heating forward path 56 is too high, the heat medium after the heat radiation flowing in the heating return path 60 is changed to the heat medium flowing in the heating forward path 56. By joining, the temperature of the heat medium sent to the heating terminal 90 can be lowered.

  The heating forward path 56 is provided with a first heating outbound path thermistor 48 and a second heating outbound path thermistor 58. The first heating forward path thermistor 48 is provided upstream of the junction where the bypass path 64 joins the heating forward path 56, and detects the temperature of the heat medium sent from the tank 30 to the heating forward path 56. The second heating forward path thermistor 58 is provided on the downstream side of the junction where the bypass path 64 joins the heating outbound path 56, and the heating medium sent from the tank 30 to the heating outbound path 56 and the bypass path 64 for heating The temperature after the heat medium sent to the forward path 56 is mixed is detected. A heating return path thermistor 62 is provided in the heating return path 60. The heating return thermistor 62 detects the temperature of the heat medium flowing in the heating return path. The first heating outward thermistor 48, the second heating outward thermistor 58 and the heating backward thermistor 62 are connected to the controller 54 of the tank unit 28. The controller 54 controls the operation of the mixing valve 66 based on the detected temperatures of the first heating forward path thermistor 48, the second heating forward path thermistor 58 and the heating backward path thermistor 62, so that the temperature of the heating medium sent to the heating terminal 90 is controlled. Can be adjusted to a desired temperature.

  FIG. 2 shows the flow of the heat medium when heating is performed while operating the heat pump unit 20. As shown in FIG. 2, a high-temperature heat medium is sent to the heating terminal 90 from the upper part of the tank 30 through the heating forward path 56. The high-temperature heat medium sent to the heating terminal 90 radiates heat at the heating terminal 90 and then returns to the lower part of the tank 30 through the heating return path 60. On the other hand, a low-temperature heat medium is sent to the heat pump unit 20 from the lower part of the tank 30 through the heat storage outbound path 34. The low-temperature heat medium sent to the heat pump unit 20 is heated in the heat pump unit 20 and then returned to the upper portion of the tank 30 through the heat storage return path 32.

  FIG. 3 shows the flow of the heating medium when the temperature of the heating medium sent from the tank 30 to the heating forward path 56 is higher than the temperature of the heating medium required by the heating terminal 90. In this case, the mixing valve 66 is controlled to increase the flow rate of the heat medium sent from the heating return path 60 to the heating outbound path 56 via the bypass path 64 and heated from the heating return path 60 via the tank 30. The flow rate of the heat medium sent to the outgoing path 56 is reduced. Thereby, the temperature of the heating medium sent from the heating forward path 56 to the heating terminal 90 can be adjusted to the temperature of the heating medium required by the heating terminal 90. Even when the temperature of the heat medium requested by the heating terminal 90 is lowered, it is possible to quickly respond to a change in the request at the heating terminal 90 without changing the heating capacity of the heat pump unit 20.

  FIG. 4 shows the flow of the heat medium when the temperature of the heat medium sent from the tank 30 to the heating forward path 56 is lower than the temperature of the heat medium required by the heating terminal 90. In this case, the heating medium flowing through the heating forward path 56 is heated by the burner 86. By adjusting the heating amount in the burner 86, the temperature of the heat medium sent from the heating forward path 56 to the heating terminal 90 can be quickly adjusted to the temperature of the heat medium required by the heating terminal 90. Even when the temperature of the heat medium requested by the heating terminal 90 rises, it is possible to respond quickly to a change in the request at the heating terminal 90 without changing the heating capacity of the heat pump unit 20.

In the hot water supply and heating system 10 of the present reference example , the heating capacity of the heat pump unit 20 is switched based on the amount of heat stored in the tank 30 while heating is performed while the heat pump unit 20 is operated. In this reference example , the heat storage amount of the tank 30 is calculated as follows.

Heat storage amount of tank 30 = ((average detection temperature of upper tank thermistor 42a, middle tank thermistor 42b, lower tank thermistor 42c and heat storage return thermistor 46) −detection temperature of heat storage forward thermistor 44) × capacity of tank 30

  The amount of heat stored in the tank 30 may be calculated as follows without using the temperature detected by the heat storage return path thermistor 46.

Heat storage amount of tank 30 = ((average detection temperature of upper tank thermistor 42a, middle tank thermistor 42b and lower tank thermistor 42c) −detection temperature of heat storage forward thermistor 44) × capacity of tank 30

In the hot water supply and heating system 10 of the present reference example , the heating capacity of the heat pump unit 20 is switched as follows based on the amount of heat stored in the tank 30.

  When the heating capacity of the heat pump unit 20 is “small” or “medium”, the heating capacity of the heat pump unit 20 is switched to “large” when the amount of heat stored in the tank 30 becomes a first predetermined value (for example, 150 kcal) or less. Thereafter, when the heat storage capacity of the tank 30 exceeds a second predetermined value (for example, 225 kcal) when the heating capacity of the heat pump unit 20 is “high”, the heating capacity of the heat pump unit 20 is switched to “medium”.

  Further, when the heating capacity of the heat pump unit 20 is “medium” or “large” and the heat storage amount of the tank 30 exceeds a third predetermined value (for example, 450 kcal), the heating capacity of the heat pump unit 20 is switched to “small”. . After that, when the heat capacity of the heat pump unit 20 is “small”, the heat capacity of the heat pump unit 20 is switched to “medium” when the amount of heat stored in the tank 30 becomes a fourth predetermined value (for example, 300 kcal) or less.

By switching the heating capability of the heat pump unit 20 as described above, the hot water supply and heating system 10 of the present reference example operates as follows. When heating at the heating terminal 90 while operating the heat pump unit 20, the heating capacity of the heat pump unit 20 is normally set to “medium”. When the heating amount in the heat pump unit 20 is smaller than the heat radiation amount in the heating terminal 90, the heat storage amount in the tank 30 decreases with time. Therefore, the amount of heat supplied to the tank 30 is increased by switching the heating capacity of the heat pump unit 20 to “large” when the amount of heat stored in the tank 30 becomes the first predetermined value or less, and the tank 30 runs out of hot water. The state is suppressed. By switching the heating capacity of the heat pump unit 20 to “large”, if the amount of heat in the heat pump unit 20 becomes larger than the amount of heat released from the heating terminal 90, the amount of heat stored in the tank 30 increases with time. When the heat storage amount of the tank 30 exceeds the second predetermined value, the heating capacity of the heat pump unit 20 is returned to “medium”.

  Unlike the above, when heating at the heating terminal 90 is performed with the heating capacity of the heat pump unit 20 as “medium”, when the heating amount in the heat pump unit 20 is larger than the heat radiation amount at the heating terminal 90 The amount of heat stored in the tank 30 increases with time. Therefore, the amount of heat supplied to the tank 30 is reduced by switching the heating capacity of the heat pump unit 20 to “small” when the amount of heat stored in the tank 30 exceeds the third predetermined value, so that the tank 30 is fully stored. Is suppressed. By switching the heating capacity of the heat pump unit 20 to “small”, when the amount of heat in the heat pump unit 20 becomes smaller than the amount of heat released in the heating terminal 90, the amount of heat stored in the tank 30 decreases with time. And when the heat storage amount of the tank 30 becomes below the fourth predetermined value, the heating capacity of the heat pump unit 20 is returned to “medium”.

As described above, in this reference example , the tank 30 is interposed between the heating terminal 90 and the heat pump unit 20, and the heating capacity of the heat pump unit 20 is switched according to the amount of heat stored in the tank 30. Since the tank 30 plays a role of buffering fluctuations in the heat dissipation amount at the heating terminal 90, it is not necessary to immediately switch the heating capability of the heat pump unit 20 to the fluctuations in the heat dissipation amount at the heating terminal 90. Even when the heating capacity of the heat pump unit 20 can be switched only in a stepwise manner, the heat radiation amount in the heating terminal 90 and the heating amount in the heat pump unit 20 can be balanced in the long term. By setting it as such a structure, the situation where the heat pump unit 20 repeats start / stop and switching of a heating capability unnecessarily can be prevented.

( Example )
The hot water supply and heating system 100 of the present embodiment has the same configuration as the hot water supply and heating system 10 of the reference example shown in FIG. 1, but the heating capacity switching method of the heat pump unit 20 is different from the hot water supply and heating system 10 of the reference example. Different. In the hot water supply and heating system 100 of the present embodiment, the heating capacity of the heat pump unit 20 is switched as follows according to the detected temperatures of the upper tank thermistor 42a, the middle tank thermistor 42b, and the lower tank thermistor 42c.

  When the heating capacity of the heat pump unit 20 is “small” or “medium”, when the detected temperature of the upper tank thermistor 42a becomes a first predetermined value (for example, 70 ° C.) or less, or the detected temperature of the middle tank thermistor 42b is When the temperature falls below the second predetermined value (for example, 30 ° C.), the heating capacity of the heat pump unit 20 is switched to “large”. Thereafter, when the heating capacity of the heat pump unit 20 is “high”, the detected temperature of the upper tank thermistor 42a exceeds a third predetermined value (for example, 75 ° C.), and the detected temperature of the middle tank thermistor 42b is the fourth predetermined value. When it exceeds (for example, 40 ° C.), the heating capacity of the heat pump unit 20 is switched to “medium”.

  When the heating capacity of the heat pump unit 20 is “medium” or “large”, the detected temperature of the middle tank thermistor 42b exceeds the fifth predetermined value (for example, 75 ° C.) and the detected temperature of the lower tank thermistor 42c is When the sixth predetermined value (for example, 40 ° C.) is exceeded, the heating capacity of the heat pump unit 20 is switched to “small”. Thereafter, when the heating capacity of the heat pump unit 20 is “low”, the detected temperature of the middle tank thermistor 42b becomes a seventh predetermined value (for example, 70 ° C.) or lower, or the detected temperature of the lower tank thermistor 42c is the eighth. When the temperature becomes a predetermined value (for example, 30 ° C.) or less, the heating capacity of the heat pump unit 20 is switched to “medium”.

  By switching the heating capacity of the heat pump unit 20 as described above, the hot water supply / heating system 10 operates as follows. When the heating amount in the heat pump unit 20 is smaller than the heat radiation amount in the heating terminal 90, the heat storage amount in the tank 30 decreases with time. Therefore, when the detected temperature of the upper tank thermistor 42a is equal to or lower than the first predetermined value, or when the detected temperature of the middle tank thermistor 42b is equal to or lower than the second predetermined value, the heating capacity of the heat pump unit 20 is “high”. By switching to, it is suppressed that the tank 30 becomes a hot water out state. By switching the heating capacity of the heat pump unit 20 to “large”, if the amount of heat in the heat pump unit 20 becomes larger than the amount of heat released from the heating terminal 90, the amount of heat stored in the tank 30 increases with time. When the detected temperature of the upper tank thermistor 42a exceeds the third predetermined value and the detected temperature of the middle tank thermistor 42b exceeds the fourth predetermined value, the heating capacity of the heat pump unit 20 is weakened to “medium”.

  Unlike the above, when the heating amount in the heat pump unit 20 is larger than the heat radiation amount in the heating terminal 90, the heat storage amount of the tank 30 increases with time. Therefore, when the detected temperature of the middle tank thermistor 42b exceeds the fifth predetermined value and the detected temperature of the lower tank thermistor 42c exceeds the sixth predetermined value, the heating capacity of the heat pump unit 20 is switched to “small”. Thus, the tank 30 is prevented from being fully stored. By switching the heating capacity of the heat pump unit 20 to “small”, when the amount of heat in the heat pump unit 20 becomes smaller than the amount of heat released in the heating terminal 90, the amount of heat stored in the tank 30 decreases with time. When the detected temperature of the middle tank thermistor 42b is equal to or lower than the seventh predetermined value or when the detected temperature of the lower tank thermistor 42c is equal to or lower than the eighth predetermined value, the heating capacity of the heat pump unit 20 is strengthened to “medium”.

  As described above, in this embodiment, the tank 30 is interposed between the heating terminal 90 and the heat pump unit 20, and the detected temperatures of the upper tank thermistor 42a, the middle tank thermistor 42b, and the lower tank thermistor 42c provided in the tank 30 are obtained. Accordingly, the heating capacity of the heat pump unit 20 is switched. Since the tank 30 plays a role of buffering fluctuations in the heat dissipation amount at the heating terminal 90, it is not necessary to immediately switch the heating capability of the heat pump unit 20 to the fluctuations in the heat dissipation amount at the heating terminal 90. Even when the heating capacity of the heat pump unit 20 can be switched only in a stepwise manner, the heat radiation amount in the heating terminal 90 and the heating amount in the heat pump unit 20 can be balanced in the long term. By setting it as such a structure, the situation where the heat pump unit 20 repeats start / stop and switching of a heating capability unnecessarily can be prevented.

  As mentioned above, although the Example of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

DESCRIPTION OF SYMBOLS 10 Hot water supply heating system 20 Heat pump unit 22 Circulation pump 24 Manual valve 28 Tank unit 30 Tank 32 Heat storage return path 34 Heat storage return path 42a Upper tank thermistor 42b Middle tank thermistor 42c Lower tank thermistor 44 Heat storage path thermistor 46 Heat storage return path thermistor 48 1st heating Outward thermistor 50 Drain pipe 52 Manual valve 54 Controller 56 Heating forward path 58 Second heating outward path thermistor 60 Heating return path 62 Heating return path thermistor 64 Bypass path 66 Mixing valve 70 Expansion tank 80 Hot water supply heating unit 82 Hot water supply pipe 84 Burner 86 Burner 87 Circulation pump 88 Controller 90 Heating terminal 100 Hot water supply and heating system

Claims (1)

A heat pump that absorbs heat from the atmosphere and heats the heat medium;
A tank for storing the heat medium,
A heat storage circuit that circulates the heat medium between the heat pump and the tank;
A heating terminal that radiates heat from the heat medium and performs heating;
A heat dissipation circuit that circulates the heat medium between the heating terminal and the tank;
An upper tank thermistor that detects the temperature of the heat medium stored in the upper part of the tank;
A middle tank thermistor that detects the temperature of the heat medium stored in the middle of the tank;
It has a lower tank thermistor that detects the temperature of the heat medium stored in the lower part of the tank.
The heating capacity of the heat pump can be switched stepwise to at least one of the first stage, the second stage stronger than the first stage, and the third stage stronger than the second stage,
When heating with a heating terminal while continuing to drive without stopping the heat pump,
When the detection capability of the upper tank thermistor is lower than the first predetermined temperature when the heating capacity of the heat pump is the first stage or the second stage, or when the detected temperature of the middle tank thermistor is lower than the second predetermined temperature, Switch the heating capacity of the heat pump to the third stage,
When the heating capacity of the heat pump is in the third stage, the heating capacity of the heat pump is increased when the detected temperature of the upper tank thermistor exceeds the third predetermined temperature and the detected temperature of the middle tank thermistor exceeds the fourth predetermined temperature. Switch to two stages,
When the heating capacity of the heat pump is in the second stage or the third stage, the detected temperature of the middle tank thermistor exceeds the fifth predetermined temperature, and the detected temperature of the lower tank thermistor exceeds the sixth predetermined temperature. Switch the heating capacity to the first stage,
When the heating capacity of the heat pump is in the first stage and the detected temperature of the middle tank thermistor is equal to or lower than the seventh predetermined temperature, or when the detected temperature of the lower tank thermistor is equal to or lower than the eighth predetermined temperature To the second stage,
The fourth predetermined temperature and the sixth predetermined temperature are higher than the second predetermined temperature and the eighth predetermined temperature, the first predetermined temperature and the seventh predetermined temperature are higher than the fourth predetermined temperature and the sixth predetermined temperature, and the third predetermined temperature. And the fifth predetermined temperature is higher than the first predetermined temperature and the seventh predetermined temperature.

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