JP5319502B2 - Heat pump heating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress degradation in efficiency of a heat pump unit without interposing a large-sized recovery tank in a heating medium heating circuit in a heat pump type heater including a tank water heating circuit 3 for circulating tank water from the bottom to the top of a hot water storage tank 1 via a radiator 23 of the heat pump unit 2, a liquid-liquid heat exchanger 41 interposed in a return conduit 4a of a heating circuit 4, and the heating medium heating circuit 5 for circulating the tank water from the top to the bottom of the hot water storage tank via the liquid-liquid heat exchanger. <P>SOLUTION: A tank water circulation amount of the heating medium heating circuit 5 is feedback controlled so that the temperature of a heating medium supplied to a heating terminal becomes a prescribed set temperature. When the temperature of the tank water after passing the liquid-liquid heat exchanger 41 exceeds a prescribed upper limit temperature, restriction control is performed for restricting the tank water circulation amount so that the temperature of the tank water does not exceed the upper limit temperature. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a heat pump heating apparatus that indirectly heats a heat medium circulated to a heating terminal by a heat pump unit.

  Conventionally, as this type of heat pump type heating device, a hot water storage tank having a water supply pipe connected to the bottom, a heat pump unit, and tank water heating in which tank water is circulated from the bottom to the top of the hot water storage tank via a heat pump unit radiator A circuit, a heating circuit that circulates the heat medium through the heating terminal, a liquid heat exchanger that is provided in a return pipe of the heating circuit that flows the heat medium that has passed through the heating terminal, and a top to bottom of the hot water storage tank What is provided with the heat-medium heating circuit which circulates tank water through a liquid heat exchanger is known (for example, refer patent document 1).

  In this case, by supplying low-temperature tank water from the bottom of the hot water storage tank to the radiator of the heat pump unit via the tank water heating circuit, the tank water can be heated and returned to the top of the hot water storage tank. Then, by supplying high-temperature tank water from the top of the hot water storage tank to the liquid heat exchanger via the heat medium heating circuit, the heat medium returned from the heating terminal can be heated and supplied to the heating terminal. .

  By the way, if the rotation speed of the tank water circulation pump provided in the heat medium heating circuit is varied to increase or decrease the tank water circulation amount of the heat medium heating circuit, the heating amount of the heat medium in the liquid-to-liquid heat exchanger will be Increase or decrease depending on the amount. Therefore, it is conceivable to feedback-control the amount of tank water circulation in the heating medium heating circuit so that the temperature of the heating medium supplied to the heating terminal becomes a predetermined set temperature. In this case, the amount of tank water circulation increases as the heating load increases and the temperature of the heat medium returned from the heating terminal decreases.

  Here, when the tank water circulation amount increases, the temperature drop amount of the tank water in the liquid heat exchanger decreases, and the relatively high temperature tank water is returned to the bottom of the hot water storage tank. Then, the temperature of the tank water supplied to the heat pump unit from the bottom of the hot water storage tank via the tank water heating circuit rises, the efficiency of the heat pump unit decreases, and finally the tank water cannot be heated by the heat pump unit. turn into.

  Therefore, in the above-described conventional example, a recovery tank into which the tank water that has passed through the liquid-liquid heat exchanger flows is interposed in the heat medium heating circuit, and the relatively low temperature tank water at the bottom of the recovery tank is stored in the hot water storage tank. It is made to return to the bottom. However, if the capacity of the recovery tank is small, the water temperature at the bottom of the tank is not sufficiently lowered, and relatively high-temperature tank water is returned to the bottom of the hot water storage tank. For this reason, the recovery tank needs to have a capacity that is about half that of the hot water storage tank (see paragraph 0092 of Patent Document 1), and there is a problem that the entire apparatus becomes large.

Japanese Patent No. 3966031 (Claim 1, paragraphs 0089 to 0105, FIG. 3)

  This invention makes it the subject to provide the heat pump type heating apparatus which enabled it to suppress the efficiency fall of a heat pump unit, without providing a large collection | recovery tank in a heat medium heating circuit in view of the above point.

  In order to solve the above problems, the present invention provides a hot water storage tank having a water supply pipe connected to the bottom, a heat pump unit, and tank water that circulates tank water from the bottom to the top of the hot water storage tank via a heat pump unit radiator. A heating circuit, a heating circuit that circulates the heating medium through the heating terminal, a liquid heat exchanger that is provided in a return pipe of the heating circuit that flows the heating medium that has passed through the heating terminal, and a top to bottom portion of the hot water storage tank A heat medium heating circuit that circulates tank water through a liquid-to-liquid heat exchanger, and a heat medium by varying a rotation speed of a tank water circulation pump provided in the heat medium heating circuit. A control means for controlling the tank water circulation amount of the heating circuit is provided, and the control means is configured so that the detected temperature of the forward temperature sensor for detecting the temperature of the heat medium supplied to the heating terminal becomes a predetermined set temperature. When feedback control is performed to control the tank water circulation rate of the medium heating circuit, and when the tank water temperature after passing through the liquid-to-liquid heat exchanger becomes higher than the predetermined upper limit temperature due to the increase in the tank water circulation rate by feedback control Is configured to perform restriction control for restricting the amount of tank water circulation so that the temperature of the tank water after passing through the liquid heat exchanger does not become higher than the upper limit temperature.

  According to the present invention, the temperature of the tank water from the heat medium heating circuit flowing into the bottom of the hot water storage tank is higher than the upper limit temperature by performing the restriction control without providing the recovery tank in the heat medium heating circuit. Can be suppressed. Therefore, the temperature boundary layer in the hot water storage tank is maintained, and relatively low temperature tank water below the upper limit temperature is supplied from the bottom of the hot water storage tank to the radiator of the heat pump unit through the tank water heating circuit. The efficiency of the heat pump unit is kept relatively high.

  Here, the upper limit value, which is the value of the tank water circulation amount at which the temperature of the tank water after passing through the liquid heat exchanger becomes the upper limit temperature, flows to the temperature of the heat medium returning from the heating terminal and to the liquid heat exchanger. It can be determined based on the flow rate of the heat medium and the temperature of the tank water supplied to the liquid heat exchanger from the top of the hot water storage tank. Therefore, a temperature sensor for detecting the temperature of the heat medium returning from the heating terminal, a flow rate sensor for detecting the flow rate of the heat medium flowing in the liquid heat exchanger, and a tank supplied to the liquid heat exchanger from the top of the hot water storage tank A temperature sensor that detects the temperature of the water, obtains the above upper limit value based on the detected values of these sensors, and when the control target value of the tank water circulation amount by feedback control exceeds the upper limit value, the tank water circulation amount is the upper limit value. It is sufficient to perform the control so as to be as the restriction control.

  In addition, when a temperature sensor that detects the temperature of the tank water after passing through the liquid-to-liquid heat exchanger is provided, the feedback control is stopped when the detected temperature of the temperature sensor becomes higher than the upper limit temperature during the feedback control. Then, the second feedback control for controlling the tank water circulation amount so that the temperature detected by the temperature sensor becomes the upper limit temperature may be performed as the limit control.

  In this case, when the detected temperature of the forward temperature sensor becomes a predetermined temperature higher than the set temperature during execution of the second feedback control, the second feedback control is stopped and the feedback control is resumed. Is desirable.

  Moreover, in this invention, it is desirable to provide the auxiliary | assistant heat source apparatus which is interposed in the heating circuit and uses the burner which heats a heat medium when the heating of a heat medium in a liquid heat exchanger is inadequate as a heat source. According to this, even if heating of the heat medium in the liquid heat exchanger occurs during the execution of the restriction control, the heat medium can be heated to the set temperature by the operation of the auxiliary heat source unit, and the heating performance is not adversely affected. .

Explanatory drawing which shows the structure of the heat pump type heating apparatus of 1st Embodiment of this invention. The flowchart which shows the control content of the tank water circulation amount performed in 1st Embodiment. The flowchart which shows the control content of the auxiliary heat source machine performed in 1st Embodiment. Explanatory drawing which shows the structure of the heat pump type heating apparatus of 2nd Embodiment of this invention. The flowchart which shows the control content of the tank water circulation amount performed in 2nd Embodiment.

  FIG. 1 shows a heat pump heating device according to a first embodiment of the present invention. This heat pump type heating device includes a hot water storage tank 1, a heat pump unit 2, a tank water heating circuit 3 for heating water (tank water) in the hot water storage tank 1 by the heat pump unit 2, and a heating medium (not shown) A heating circuit 4 that circulates water, an antifreeze liquid, and the like, and a heating medium heating circuit 5 that heats the heating medium with hot tank water stored in the hot water storage tank 1.

  The hot water storage tank 1 is a tank having a longitudinal capacity of, for example, 50 L in the vertical direction. A water supply channel 11 is connected to the bottom of the hot water storage tank 1, and a hot water supply channel 12 is connected to the top. A first water amount adjustment valve 13 is provided in the water supply passage 11, and a branched water supply passage 11 a branched from a portion of the water supply passage 11 upstream of the first water amount adjustment valve 13 is discharged through the second water amount adjustment valve 14. Connected to the road 12. And the mixing ratio of the high temperature water from the hot water storage tank 1 and the cold water from the branch water supply path 11a is adjusted by both the first and second water amount control valves 13 and 14, and the outlet tap ( Hot water having a set temperature is discharged from a not-shown).

  A hot water supply auxiliary heat source unit 15 having a burner 15a as a heat source and a bypass valve 16 in parallel with the burner 15a are provided in a portion of the hot water supply channel 12 downstream of the connecting portion of the branch water supply channel 11a. When the temperature of the water supplied from the hot water storage tank 1 becomes lower than the set temperature, the bypass valve 16 is closed and the auxiliary heat source unit 15 is operated, and the auxiliary heat source unit 15 heats the water to the set temperature. Like to do.

  The heat pump unit 2 is a publicly known unit configured by a closed circuit that returns the refrigerant from the evaporator 21 to the evaporator 21 via the compressor 22, the radiator 23, and the expansion valve 24. The evaporator 21 is provided with a fan 21a, and the refrigerant absorbs heat from the atmosphere blown by the fan 21a and evaporates. The evaporated refrigerant is compressed by the compressor 22 to become high temperature and high pressure, radiated by the radiator 23, depressurized by the expansion valve 24, and returned to the evaporator 21.

  The tank water heating circuit 3 is a circuit that circulates tank water from the bottom to the top of the hot water storage tank 1 through the radiator 23 of the heat pump unit 2. A tank water circulation pump 31 is interposed in the tank water heating circuit 3 in series with the radiator 23. Then, by the operation of the circulation pump 31, low-temperature tank water is supplied from the bottom of the hot water storage tank 1 to the radiator 23, and the tank water is heated by heat exchange with the refrigerant in the radiator 23 and returned to the top of the hot water storage tank 1. Then, hot water close to 90 ° C. is stored in the upper part of the hot water storage tank 1 with the lower low temperature water and the temperature boundary layer. When the amount of high-temperature water in the hot water storage tank 1 becomes a predetermined amount or less, the heat pump unit 2 is operated and the circulation pump 31 is operated to perform the tank water heating operation.

  The heating circuit 4 is provided with a return pipe 4a for flowing the heat medium that has passed through the heating terminal, and the return pipe 4a, in order from the upstream side (heating terminal side), a liquid-to-liquid heat exchanger 41, A cistern 42, a heating pump 43, and an auxiliary heat source unit 44 for heating using a burner 44a as a heat source are interposed. As the heating terminal, there are a high-temperature heating terminal such as a bathroom heater and a low-temperature heating terminal such as floor heating. Then, in addition to the return pipe 4a connected to the high-temperature heating terminal and the low-temperature heating terminal, the high-temperature forward pipe 4b that supplies the heat medium that has passed through the auxiliary heat source unit 44 to the high-temperature heating terminal. The low-temperature forward conduit 4c that supplies the heat medium from the downstream side of the heating pump 43 to the low-temperature heating terminal without passing through the auxiliary heat source unit 44, and the heat medium that has passed through the auxiliary heat source unit 44 is directly returned to the systern 42. A bypass line 4d provided with a valve 45 is provided.

  In the present embodiment, as the auxiliary heat source unit 15 for hot water supply and the auxiliary heat source unit 44 for heating, a hot water supply heat source unit and a heating heat source unit of a general gas composite heat source machine having hot water supply and heating functions are used. ing.

  The heat medium heating circuit 5 is a circuit that circulates tank water from the top to the bottom of the hot water storage tank 1 via a liquid-liquid heat exchanger 41. In the heat medium heating circuit 5, a tank water circulation pump 51 is interposed in series with the liquid heat exchanger 41. Then, by the operation of the circulation pump 51, high-temperature tank water is supplied from the top of the hot water storage tank 1 to the liquid heat exchanger 41, the heat medium is heated by heat exchange with the tank water, and the tank water after heat exchange is It is returned to the bottom of the hot water storage tank 1.

Moreover, the heat pump type heating apparatus includes a controller 6 as control means. The controller 6, the forward first temperature sensor 7 serving as a temperature sensor ₁ for detecting the temperature of the heat medium flowing through the cold forward pipe line 4c of the heating circuit 4 (heat medium supplied to the low temperature heating terminal), the heating circuit 4 and forward temperature sensor serving as the second temperature sensor 7 ₂ for detecting the temperature of the heat medium (the heat medium supplied to the high temperature heating terminal) flowing through the hot forward pipe line 4b, the heat medium flowing through the return line 4a of the heating circuit 4 a third temperature sensor 7 ₃ for detecting the temperature, the fourth temperature sensor 7 ₄ for detecting the temperature of the tank water supplied to the liquid-liquid heat exchanger 41 from the top of the hot water storage tank 1, the return line of the heating circuit 4 A detection signal is input to the flow rate sensor 8 that detects the flow rate of the heat medium flowing in the liquid-to-liquid heat exchanger 41 that is provided in 4a.

Here, if the rotation speed of the circulation pump 51 is varied to increase or decrease the tank water circulation amount of the heat medium heating circuit 5, the heating amount of the heat medium in the liquid heat exchanger 41 is increased or decreased according to the tank water circulation amount. . Therefore, the controller 6 is at a high temperature heating operation of circulating the heat medium in the low-temperature heating operation or during a high temperature heating terminal which circulates the heat medium in the low temperature heating terminal, the first temperature sensor ₇₁ and second temperature sensor 7 ₂ detected temperature There predetermined set temperature (e.g., low temperature heating operation temperature detected by the first temperature sensor ₇₁ is 60 ° C., the high temperature heating operation temperature detected by the second temperature sensor 7 ₂ 80 ° C.) so that the heat Feedback control for controlling the tank water circulation amount of the medium heating circuit 5 is performed.

  By the way, if the tank water circulation amount of the heat medium heating circuit 5 is feedback-controlled, the tank water circulation amount increases as the heating load increases and the temperature of the heat medium flowing through the return pipe 4a decreases. When the tank water circulation amount increases, the temperature drop amount of the tank water in the liquid heat exchanger 41 decreases, and the relatively high temperature tank water is returned to the bottom of the hot water storage tank 1. Then, the temperature boundary layer in the hot water storage tank 1 is disturbed, the temperature of the tank water supplied from the bottom of the hot water storage tank 1 to the heat pump unit 2 through the tank water heating circuit 3 rises, and the efficiency of the heat pump unit 2 is increased. The tank water will eventually become impossible to heat by the heat pump unit 2.

  Therefore, in the present embodiment, when the temperature of the tank water after passing through the liquid-to-liquid heat exchanger 41 becomes higher than a predetermined upper limit temperature (for example, 60 ° C.) due to an increase in the tank water circulation amount by feedback control, Limit control is performed to limit the amount of tank water circulation so that the temperature of the tank water after passing through the liquid-liquid heat exchanger 41 does not become higher than the upper limit temperature.

Hereinafter, the control of the tank water circulation amount by the controller 6 will be described in detail with reference to FIG. First, in STEP1, obtains the control target value YQt the tank water circulating amount PDI control method from the deviation between the set temperature and the first temperature sensor ₇₁ for detecting the temperature TH1 or the second temperature sensor ₇ and _second detected temperature TH2. Next, an upper limit value that is the value of the tank water circulation amount at which the temperature of the tank water after passing through the liquid-to-liquid heat exchanger 41 is the upper limit temperature is determined in STEP2.

The upper limit, the third temperature sensor 7 ₃ detected temperature TH3 (the temperature of the heat carrier returning from the heating terminal), detected flow Qn of the flow rate sensor 8 (the flow rate of the heat medium flowing through the liquid-liquid heat exchanger 41), can be obtained from the fourth temperature detected by the temperature sensor 7 ₄ TH4 (temperature of the tank water supplied to the liquid-liquid heat exchanger 41 from the top of the hot water storage tank 1). Here, if there is no heat dissipation loss to the outside in the liquid heat exchanger 41 (actually, the heat dissipation loss is negligibly small), the heat passage rate of the liquid heat exchanger 41 is K, the liquid heat exchanger. The heat transfer area of 41 is A, the temperature of the heat medium after passing through the liquid-liquid heat exchanger 41 is TH0, the circulation amount of tank water is Qt, and the temperature of the tank water after passing through the liquid-liquid heat exchanger 41 is It is known that the following formulas (1) and (2) are established as TH5. In the equation (1), ln is a natural logarithm.
(TH0-TH3) .Qn = K.A. {(TH4-TH0)-(TH5-TH3)} / ln {(TH4-TH0) / (TH5-TH3)} (1)
(TH0-TH3) * Qn = (TH4-TH5) * Qt (2)
From equation (2), TH0 = TH3 + (TH4-TH5) · Qt / Qn is substituted into (1) and the upper limit temperature is substituted as TH5, and the value of Qt obtained by convergence calculation is the upper limit value. Become.

Actually, since the heat transfer rate K changes depending on Qn and Qt, the upper limit value cannot be accurately obtained from the above equation, and the convergence calculation takes time, so that the cycle of feedback control is short. It is difficult to obtain the upper limit value during time. Therefore, in this embodiment, the controller and the third temperature sensor 7 ₃ detected temperature TH3, and detected flow Qn of the flow rate sensor 8, a data table for determining the upper limit value and the detected temperature TH4 of the fourth temperature sensor 7 ₄ as parameters 6 and the upper limit value is obtained by table search.

Once the upper limit value is obtained as described above, it is next determined in STEP 3 whether or not the control target value YQt is equal to or lower than the upper limit value. When YQt ≦ the upper limit value, the process proceeds to STEP 4, the rotational speed of the circulation pump 51 is controlled so that the actual tank water circulation amount Qt becomes the control target value YQt, and the process returns to STEP 1. Then, by treatment with STEP1-4, as the first temperature sensor ₇₁ for detecting the temperature TH1 or the second temperature sensor _{7 and second} detected temperature TH2 is set temperature, the tank water circulation amount Qt is feedback controlled.

  On the other hand, when it is determined in STEP3 that YQt> the upper limit value, the process proceeds to STEP5, the rotational speed of the circulation pump 51 is controlled so that the actual tank water circulation amount Qt becomes the upper limit value, and the process returns to STEP1.

  According to this, it is possible to prevent the temperature of the tank water from the heat medium heating circuit 5 flowing into the bottom of the hot water storage tank 1 from becoming higher than the upper limit temperature by the processing in STEP 5 being the above limit control. Therefore, the temperature boundary layer in the hot water storage tank 1 is maintained, and relatively low temperature tank water below the upper limit temperature is supplied from the bottom of the hot water storage tank 1 to the radiator 23 of the heat pump unit 2 via the tank water heating circuit 3. Therefore, the efficiency of the heat pump unit 2 is maintained relatively high.

  It should be noted that the heating of the heat medium is delayed only by heating by the liquid heat exchanger 41, and if the restriction control is performed, the heating of the heat medium by the liquid heat exchanger 41 is insufficient, Cannot be heated to the set temperature. Therefore, the controller 6 also controls the auxiliary heat source unit 44 for heating in parallel with the control of the tank water circulation amount described above.

Control contents of the auxiliary heat source unit 44 is as shown in FIG. 3, STEP 11 by the first temperature sensor ₇₁ for detecting the temperature TH1 or the second temperature sensor _{7 and second} detection temperature TH2 is set temperature than the predetermined temperature Delta] T1 (e.g. 12 ° C. ) and when it is determined to have become more low, is lower the first temperature sensor ₇₁ for detecting the temperature TH1 or the second temperature sensor _{7 and second} detected temperature TH2 is a predetermined temperature than the set temperature Delta] T2 (e.g. 5 ° C.) or higher in STEP12 When it is determined that a predetermined time (for example, 3 minutes) has passed, the process proceeds to STEP 13 where the burner 44a of the auxiliary heat source unit 44 is ignited and the heat medium is also heated by the auxiliary heat source unit 44. Then, if it is determined that the first temperature sensor ₇₁ for detecting the temperature TH1 or the second temperature sensor _{7 and second} detection temperature TH2 is set a predetermined temperature than the temperature ΔT3 it becomes (e.g., 5 ° C.) higher in STEP 14, the routine proceeds to STEP15 To extinguish the burner 44a.

Next, the heat pump type heating apparatus of 2nd Embodiment shown in FIG. 4 is demonstrated. Structural differences from the first embodiment of the second embodiment includes a third temperature sensor 7 ₃ and a fourth temperature sensor 7 ₄ and the flow rate sensor 8 is omitted, has passed through the liquid-liquid heat exchanger 41 5 in that a temperature sensor 7 ₅ for detecting the temperature of the tank water after.

Moreover, in 2nd Embodiment, control of the tank water circulation amount by the controller 6 is performed as shown in FIG. In this control, first, in STEP 21, the first temperature sensor ₇₁ for detecting the temperature TH1 or the second temperature sensor _{7 and second} control target value YQt detected temperature TH2 and the set temperature and the tank water circulation amount PDI control method from the deviation of Ask. Then, the process proceeds to STEP 22, the detection temperature TH5 fifth temperature sensor _{7 5} is equal to or smaller than a maximum temperature described above. If TH5 ≦ upper limit temperature, the process proceeds to STEP23, the rotational speed of the circulation pump 51 is controlled so that the actual tank water circulation amount Qt becomes the control target value YQt, and the process returns to STEP21. Then, by treatment with STEP21-23, as the first temperature sensor ₇₁ for detecting the temperature TH1 or the second temperature sensor _{7 and second} detected temperature TH2 is set temperature, the tank water circulation amount Qt is feedback controlled.

On the other hand, when it is TH5> upper limit temperature, the process proceeds to STEP 24, and stops the feedback control, the second detected temperature TH5 fifth temperature sensor 7 ₅ controls the tank water circulation quantity Qt to provide up to a temperature Perform feedback control. Next, it is determined whether or not the first temperature sensor ₇₁ for detecting the temperature TH1 or the second temperature sensor _{7 and second} detected temperature TH2 is higher predetermined temperature .DELTA.T4 (e.g., 2 ° C.) or higher than the set temperature at STEP 25, Until it becomes higher, the process returns to STEP 24 to continue the second feedback control. Meanwhile, when the first temperature sensor ₇₁ for detecting the temperature TH1 or the second temperature sensor _{7 and second} detected temperature TH2 is higher predetermined temperature ΔT4 more than the set temperature, the process returns to STEP 21, it stops the second feedback control Then, the above-described feedback control is resumed.

  Also in 2nd Embodiment, it can suppress that the temperature of the tank water from the heat-medium heating circuit 5 which flows into the bottom part of the hot water storage tank 1 becomes higher than upper limit temperature. Therefore, relatively low-temperature tank water below the upper limit temperature is supplied from the bottom of the hot water storage tank 1 to the radiator 23 of the heat pump unit 2 via the tank water heating circuit 3, and the efficiency of the heat pump unit 2 is relatively high. Highly maintained. In the second embodiment as well, the auxiliary heat source unit 44 for heating is controlled with the same control contents as in FIG. 3 described above.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to this. For example, although the high temperature heating terminal and the low temperature heating terminal are provided as the heating terminal in the above embodiment, the present invention can be similarly applied to the case where only one of the high temperature heating terminal and the low temperature heating terminal is provided. In addition, the auxiliary heat source unit 44 for heating can be omitted.

DESCRIPTION OF SYMBOLS 1 ... Hot water storage tank, 11 ... Water supply path, 2 ... Heat pump unit, 23 ... Radiator, 3 ... Tank water heating circuit, 4 ... Heating circuit, 4a ... Return line, 41 ... Liquid heat exchanger, 44 ... Auxiliary heat source 44a ... burner, 5 ... heat medium heating circuit, 51 ... circulation pump, 6 ... controller, 7 ₁ ... first temperature sensor (outward temperature sensor for detecting the temperature of the heat medium supplied to the low temperature heating terminal), 7 ₂ 2nd temperature sensor (outward temperature sensor for detecting temperature of heat medium supplied to high temperature heating terminal), 7 ₃ ... 3rd temperature sensor (temperature sensor for detecting temperature of heat medium returning from heating terminal), 7 ₄ ... 4th temperature sensor (temperature sensor which detects the temperature of the tank water supplied to the liquid heat exchanger from the top of the hot water storage tank), 7 ₅ ... 5th temperature sensor (tank water after passing through the liquid heat exchanger) Temperature sensor to detect the temperature of 8) Flow rate sensor.

Claims (2)

A hot water storage tank having a water supply pipe connected to the bottom, a heat pump unit, a tank water heating circuit that circulates tank water from the bottom to the top of the hot water storage tank via a heat pump unit radiator, and a heating medium via a heating terminal Circulating heating circuit, liquid-liquid heat exchanger installed in the return line of the heating circuit that flows the heating medium that passed through the heating terminal, and tank water from the top to the bottom of the hot water tank via the liquid-liquid heat exchanger In a heat pump heating device comprising a circulating heat medium heating circuit,
A control means for controlling the tank water circulation amount of the heat medium heating circuit by changing the rotation speed of the tank water circulation pump interposed in the heat medium heating circuit;
The control means performs feedback control for controlling the tank water circulation amount of the heating medium heating circuit so that the detected temperature of the forward temperature sensor for detecting the temperature of the heating medium supplied to the heating terminal becomes a predetermined set temperature. If the tank water temperature after passing through the heat exchanger becomes higher than the predetermined upper limit temperature due to the increase in the tank water circulation rate by feedback control, the tank water temperature after passing through the liquid-liquid heat exchanger will become the upper limit. It is configured to perform limit control to limit the amount of tank water circulation so as not to rise above the temperature ,
A temperature sensor for detecting the temperature of the heat medium returning from the heating terminal, a flow sensor for detecting the flow rate of the heat medium flowing in the liquid heat exchanger, and tank water supplied to the liquid heat exchanger from the top of the hot water storage tank A temperature sensor that detects the temperature, and based on the detection values of these sensors, obtain an upper limit value that is a value of the tank water circulation amount at which the temperature of the tank water after passing through the liquid heat exchanger becomes the upper limit temperature, When the control target value of the tank water circulation amount by the feedback control exceeds the upper limit value, the restriction control is performed to control the tank water circulation amount to be the upper limit value . Wherein interposed in the heating circuit, the liquid-liquid claim 1 Symbol for heating of the heat medium in the heat exchanger is a burner for heating the heat medium when insufficient characterized in that it comprises an auxiliary heat source apparatus for a heat source Heat pump type heating device.

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