JP2005024241A - Heat pump type hot-water supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat pump type hot-water supply device capable of increasing the energy efficiency by effectively utilizing a hot water at the middle part in a hot water tank. <P>SOLUTION: This heat pump type hot-water supply device is provided with a heat pump refrigerant circuit X using carbon dioxide as a refrigerant and a water circulation circuit N for hot water supply which circulates water at the bottom part in the hot water tank 26 to a refrigerant-to-water heat exchanger 27 and heats and returns the hot water heated by the refrigerant-to-water heat exchanger 27 to the top of the hot water tank 26 to store the hot water in the hot water tank 26. And, it is constituted so that a top hot water delivery pipe 40 is connected to the top of the hot water tank and an intermediate hot water delivery pipe 33 is connected to the intermediate part of the hot water tank, and the top hot water delivery pipe and the intermediate hot water delivery pipe are merged at a merging part G, and a first mixing valve 100 mixing high temperature hot water from the top hot-water supply pipe with intermediate temperature hot water from the intermediate delivery pipe is installed at the merging part and a second mixing valve 57 mixing hot water from the hot water supply pipe with city water from a city water pipe 62 is installed in the hot water supply pipe on the downstream side from the first mixing valve. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heat pump type hot water supply apparatus that heats water with refrigerant heat and can store hot water in a hot water supply tank.

  2. Description of the Related Art Conventionally, a heat pump type hot water supply apparatus has been proposed in which a hot water supply heat exchanger heats water with refrigerant heat and can store hot water in a hot water supply tank (see Patent Document 1).

  With the thing of the said patent document 1, although it is possible to raise the temperature of the hot water stored in a hot water supply tank to 60 degreeC or more, for example, it is difficult to raise temperature significantly more than it. Therefore, when the refrigerant containing a large amount of carbon dioxide is used as the refrigerant, the temperature of the hot water stored in the hot water supply tank can be increased to, for example, about 90 ° C. because the refrigerant pressure is higher than that of the chlorofluorocarbon refrigerant. Is possible.

Generally, in a heat pump type hot water supply device, the hot water temperature at the top of the hot water tank is higher than the others, so a hot water pipe is connected to this top, and water is mixed with the hot water supplied through this to make the temperature appropriate. Hot water is supplied above.
JP-A-11-193958

  By the way, in the heat pump type hot water supply apparatus described in Patent Document 1, since the hot water temperature at the top of the hot water supply tank becomes high, a hot water supply pipe is connected to the top and water is mixed with the hot water supplied through this pipe. And hot water after making the temperature appropriate. However, when the hot water temperature of the hot water supply tank is high, it is necessary to mix a large amount of water with this hot water, and there is a problem that the energy efficiency of this heat pump hot water supply device is lowered.

  The present invention has been made in consideration of the above-described circumstances, and provides a heat pump type hot water supply apparatus capable of improving energy efficiency by effectively using hot water in an intermediate portion in a hot water supply tank.

  The present invention described in claim 1 is a heat pump refrigerant circuit comprising a compressor, a heat pump heat exchanger, and a refrigerant-to-water heat exchanger connected in a loop with refrigerant piping, and using carbon dioxide as a refrigerant, A hot water tank, a circulation pump, and a refrigerant-to-water heat exchanger are connected in a loop by a hot water supply water pipe, and water at the bottom in the hot water tank is circulated through the refrigerant-to-water heat exchanger to heat it. A hot-water supply water circulation circuit that allows hot water heated by the heat exchanger to be returned to the top of the hot-water supply tank and stored in the hot-water supply tank; An intermediate hot water pipe is connected to the intermediate part of the tank, and hot water from the upper hot water pipe and intermediate hot water from the intermediate hot water pipe are joined to the junction of the upper hot water pipe and the intermediate hot water pipe. A first mixing valve is installed to mix , To the first downstream side of the hot water supply pipe than mixing valves, characterized in that a second mixing valve for mixing the tap water from the hot water and tap water piping from the hot water supply pipe.

  Moreover, the present invention described in claim 2 is the heat pump hot water supply apparatus according to claim 1, wherein the first mixing valve is a wax valve.

  In the present invention, by using carbon dioxide as the refrigerant of the heat pump refrigerant circuit, the temperature of the water heated by the refrigerant-to-water heat exchanger is high, and the temperature of the hot water stored in the hot water supply tank can be raised to a high temperature. Of course, the intermediate temperature hot water supplied through the intermediate outlet piping and the hot water supplied through the top outlet piping are mixed by the first mixing valve and mixed by the first mixing valve. Hot water and tap water from the tap water pipe are mixed with the second mixing valve to supply hot water, effectively using hot water at an intermediate temperature in the hot water tank, and high temperature in the top of the hot water tank Unnecessary boiling due to excessive removal of hot water can be suppressed, and energy efficiency can be improved.

  The present invention comprises a compressor, a refrigerant-to-water heat exchanger, and a heat pump heat exchanger connected in a loop with refrigerant piping, and a heat pump refrigerant circuit using carbon dioxide as a refrigerant, a hot water supply tank, a circulation pump, A refrigerant-to-water heat exchanger is connected in a loop with a hot water supply water pipe, and water at the bottom in the hot water tank is circulated through the refrigerant-to-water heat exchanger and heated, and is heated by this refrigerant-to-water heat exchanger. A hot water supply water circulation circuit that allows the hot water to be returned to the top of the hot water tank and stored in the hot water tank, and connected to the top of the hot water tank with a hot water outlet piping, and in the middle of the hot water tank First hot water pipes are connected, and hot water from the upper hot water pipes and intermediate hot water from the intermediate hot water pipes are mixed at the junction of the upper hot water pipe and the intermediate hot water pipe. A mixing valve is provided and this first mixing A hot water supply pipe downstream of the valve is provided with a second mixing valve for mixing hot water from the hot water supply pipe and tap water from the tap water pipe. One embodiment of the present invention will be described below. To do.

  An embodiment of the present invention will be described below with reference to FIGS.

  FIG. 1 shows an embodiment of a heat pump type hot water supply apparatus according to the present invention, and is a circuit diagram when water in a hot water supply tank is heated and hot water is stored in the tank.

  As shown in FIG. 1, the heat pump type hot water supply apparatus 10 includes a heat pump unit 11, a hot water supply unit 12, a faucet 13, a bathtub 14, and control devices 15A and 15B.

  The heat pump unit 11 includes a compressor 16, a hot water supply heat exchanger (refrigerant-to-water heat exchanger) 27, a heat pump heat exchanger 18, and an accumulator 17 that are sequentially arranged and connected in a loop through a refrigerant pipe 19. A refrigerant circuit X is provided. The compressor 16 compresses the refrigerant. The hot water supply heat exchanger 27 heats hot water or water by the heat of the refrigerant discharged from the compressor 16. In this embodiment, a refrigerant containing a large amount of carbon dioxide is used as the refrigerant. That is, the heat pump refrigerant circuit X uses carbon dioxide as a refrigerant. Thus, when carbon dioxide is used as the refrigerant, the refrigerant pressure is usually higher than that of the chlorofluorocarbon refrigerant.

  The aforementioned hot water supply unit 12 includes a hot water supply tank 26, a bathtub heat exchanger (water-to-water heat exchanger) 28, a faucet hot water supply line 71, a bathtub pouring line 72, and the like.

  The hot water supply tank 26 stores hot water heated by refrigerant heat using a hot water supply heat exchanger 27. The hot water supply tank 26 and the hot water supply heat exchanger 27 are connected in a loop by a hot water supply water pipe 36 provided with a hot water supply circulation pump 34, a flow rate adjusting valve 35, and a first switching electromagnetic valve 73. When the valve 73 is opened, as shown by the thick line in FIG. 1, a hot water supply water circulation circuit N for circulating water is configured.

  When carbon dioxide is used as the refrigerant, as described above, the refrigerant pressure becomes higher than that of the chlorofluorocarbon refrigerant, and the temperature of the hot water stored in the hot water supply heat exchanger 27 rises to about 90 ° C.

  Since the heat pump unit 11 and the hot water supply unit 12 are connected in a loop shape by the hot water supply water pipe 36, compared to the conventional case, the high pressure refrigerant pipe (for example, the refrigerant pipe 19) is not exposed to the outside, and the heat pump hot water supply apparatus. Safety can be improved.

  A first tap water pipe 38 provided with a pressure reducing check valve 37 is connected to the bottom portion 26 </ b> B of the hot water supply tank 26 so that tap water can be always supplied into the hot water supply tank 26. Therefore, tap water pressure always acts in the hot water supply tank 26.

  Further, the top 26A of the hot water supply tank 26 is connected to a top hot water discharge pipe 40 having a pressure relief valve 39. The intermediate portion 26C between the top 26A and the bottom 26B of the hot water tank 26 has an intermediate hot water supply. A pipe 33 is connected, and a mixing valve 100 such as a wax valve serving as a first mixing valve is disposed at the junction of the hot water pipes 33 and 40.

  When the water in the bottom portion 26B of the hot water supply tank 26 is supplied to the hot water supply heat exchanger 27 by the operation of the hot water supply circulation pump 34, the hot water supply heat exchanger 27 converts the supplied water into the heat pump unit 11. The refrigerant 16 is heated by the heat of the refrigerant gas discharged from the compressor 16. When the first switching solenoid valve 73 is opened, the heated hot water or water is adjusted in flow rate by the flow rate adjusting valve 35 and guided to the top 26A of the hot water supply tank 26, and has an upper limit of about 90 ° C. in the hot water supply tank 26. Hot water can be stored.

  The pressure relief valve 39 releases the pressure when hot water or water is heated excessively and the pressure in the hot water supply tank 26 becomes excessive.

  The bathtub heat exchanger 28 is a water-to-water heat exchanger that circulates hot water in the hot water supply tank 26 to replenish hot water in the bathtub 14. Hot water in the hot water supply tank 26 is pumped out by driving the pump 102 in the circulation pipe 101 led out from the top portion 26A. The pumped hot water is led to the bathtub heat exchanger 28 through the circulation pipe 101 to heat (repel) the hot water or water in the bathtub 14, and then the second switching solenoid valve 74 and the return It returns to the intermediate part 26C between the top part 26A and the bottom part 26B of the hot water tank 26 through the pipe 103.

  That is, the bathtub heat exchanger 28 is brought into contact with the introduction water pipe 75 that guides hot water in the hot water supply tank 26 and the first bathtub water pipe 51 that guides hot water or water in the bathtub 14. And the hot water or water respectively flowing through the first bathtub water pipe 51 are configured to be able to exchange heat. The introduction water pipe 75 and the first bathtub water pipe 51 are formed in a flat tube shape in the portion constituting the bathtub heat exchanger 28 and the contact area is increased.

  The first bathtub water pipe 51 communicating the bathtub heat exchanger 28 and the bathtub 14 includes a bathtub circulation pump 46, a filter 47, a water level sensor 48, a thermistor 49, and a flow switch 50.

  This first bathtub water pipe 51 constitutes a bathtub water circulation circuit P in which hot water or water circulates between the bathtub heat exchanger 28 and the bathtub 14.

  Since the water level sensor 48 communicates with the bathtub 14 via the first bathtub water pipe 51, the water level sensor 48 detects the level of hot water or water in the bathtub 14. Further, the thermistor 49 detects the hot water temperature when the hot water or water is circulating in the bathtub water circulation circuit P, and indirectly detects the hot water temperature in the bathtub 14. Moreover, the flow switch 50 detects that hot water or water is circulating in the water circulation circuit P for bathtubs. Further, the filter 47 filters hot water together with a filter (not shown) disposed in the bathtub 14.

  As described later, hot water is poured into the bathtub 14 to fill the bathtub 14, and when the hot water in the bathtub 14 is replenished, the circulation pump 102 and the bathtub circulation pump 46 are operated. Then, as shown by the thick line in FIG. 4, the hot water in the hot water supply tank 26 and the hot water in the bathtub 14 flow into the bathtub heat exchanger 28, where heat is exchanged, and the hot water in the bathtub 14 is The hot water in the hot water supply tank 26 is chased away. The hot water worked in the bathtub heat exchanger 28 is lowered to about 50 ° C. by the heat exchange, and flows into the intermediate portion 26 </ b> C of the hot water supply tank 26 through the water pipe 103.

  The faucet hot water supply line 71 includes a hot water supply pipe 59, a mixing control valve 57 as a second mixing valve provided in the hot water supply pipe 59 on the downstream side of the mixing valve 100, and a flow sensor 58, as indicated by a thick line Q in FIG. It is configured with. Since the tap water pressure is applied to the hot water supply tank 26 via the first tap water pipe 38, the hot water in the hot water supply tank 26 can be supplied to the tap 13 by opening the tap 13.

  The flow sensor 58 detects the amount of hot water flowing through the hot water supply pipe 59. Further, the mixing control valve 57 as the second mixing valve is disposed downstream of the pressure reducing check valve 37 of the first tap water pipe 38 through the second tap water pipe 62 as shown by a thick line R in FIG. Connected.

  Therefore, by controlling the opening degree of the mixing control valve 57, the hot water from the hot water supply pipe 59 and the tap water from the second tap water pipe 62 are mixed, and the hot water supplied from the faucet 13 is about 60 ° C. or less, for example 42 Adjusted to ° C.

  As shown by the thick line S in FIG. 3, the bathtub pouring line 72 is provided between the downstream side of the flow sensor 58 in the hot water supply pipe 59 and the space between the bathtub circulation pump 46 and the flow switch 50 in the first bathtub water pipe 51. The hot water in the hot water supply tank 26 can be poured into the bathtub 14 by being connected by the bathtub water pipe 68. In the second bathtub water pipe 68, a flow sensor 64, a pouring electromagnetic valve 65, a relief means 66, a check valve 67, and an electromagnetic valve 54 are sequentially arranged from the hot water supply pipe 59 side.

  Here, the flow sensor 64 detects the amount of hot water flowing in the second bathtub water pipe 68. The relief means 66 and the check valve 67 release pressure when excessively heated hot water flows through the second bathtub water pipe 68. The solenoid valve 54 is opened when hot water is supplied to the bath, and is closed when reheating.

  When the hot water solenoid valves 65 and 54 are opened while the bathtub circulation pump 46 is stopped, the hot water in the hot water supply tank 26 becomes part of the hot water supply pipe 59 and The second bathtub water pipe 68 flows into the first bathtub water pipe 51 and is poured into the bathtub 14 through the flow switch 50, the thermistor 49, the water level sensor 48, and the filter 47 in the first bathtub water pipe 51. .

  When the water level sensor 48 detects that a proper amount of hot water has been poured into the bathtub 14 from the hot water supply tank 26, the hot water solenoid valves 65 and 54 are closed. Thereafter, when the thermistor 49 detects that the temperature of the hot water in the bathtub 14 has fallen below the appropriate temperature, the hot water or the water in the bathtub 14 is heated (fired) as described above, and the hot water in the bathtub 14 is heated. Is kept warm.

  In this way, an operation in which an appropriate amount of hot water is poured from the hot water supply tank 26 into the bathtub 14 and then the hot water in the bathtub 14 is heated to an appropriate temperature for a predetermined time (retreating) is referred to as automatic bath operation. .

  In the above-described embodiment, since the heat pump refrigerant circuit X using carbon dioxide as the refrigerant is provided, the temperature of the hot water stored in the hot water supply tank 26 is about 90 ° C. as compared with the refrigerant circuit using the fluorocarbon refrigerant. Will rise significantly. According to this, by circulating the hot water in the hot water supply tank 26, the hot water in the bathtub 14 can be replenished with this hot water temperature. Therefore, in the case of chasing a bath without supplying hot water, it is not necessary to operate the heat pump unit 11 and energy efficiency can be improved.

  The control device 15A is installed in the heat pump unit 11, and controls the operation (including capacity control) and stop of the compressor 16. The control device 15B is installed in the hot water supply unit 12 to operate or stop the hot water supply circulation pump 34 and the bathtub circulation pump 46, the first switching electromagnetic valve 73, the second switching electromagnetic valve 74, and the hot water supply electromagnetic valve. The opening and closing of the flow control valve 35 and the mixing control valve 57 are controlled. The control device 15B is connected to the control device 15A of the heat pump unit 11 by a communication line 78, enables bidirectional communication, and is connected to the remote controller 79 in a wired or wireless state.

  With the configuration described above, according to the above-described embodiment, for example, the following operational effects can be obtained.

  A hot water supply heat exchanger 27 that heats water with refrigerant heat and can store hot water in the hot water supply tank 26 is disposed in the heat pump unit 11 including the compressor 16 that compresses the refrigerant, and the hot water supply tank 26 is the hot water supply unit. 12, the heat exchanger 28 for the bathtub is configured to heat the hot water or water in the bathtub 14 by the heat of the hot water heated by the hot water supply heat exchanger 27, so that the heat can be kept. Since the refrigerant pipe 19 through which the high-pressure refrigerant flows is disposed only in the heat pump unit 11 and is not disposed between the heat pump unit 11 and the hot water supply unit 12, these high-pressure refrigerant pipes are exposed to the outside. Can be prevented, and the safety of the heat pump hot water supply apparatus 10 can be improved.

  The bathtub heat exchanger 28 is a portion corresponding to the bathtub heat exchanger 28, that is, an introduction water pipe 75 that guides hot water in the hot water supply tank 26 and a first bathtub water pipe 51 that guides hot water or water in the bathtub 14. Since the hot water or water flowing through both pipes (introductory water pipe 75 and first bathtub water pipe 51) can be exchanged by heat, the heat pump unit 11 is operated at the time of bathing. There is no need to improve energy efficiency. Moreover, even if one piping is damaged among both piping (introduction water piping 75 and the 1st bathtub water piping 51), the other piping is not influenced by it. For example, even if the first bathtub water pipe 51 is damaged, for example, contaminated hot water or water in the first bathtub water pipe 51 is not mixed into the hot water or water in the introduction water pipe 75. Since the contaminated hot water does not flow into the hot water supply tank 26 through the first bathtub water pipe 51, the hot water or water in the hot water supply tank 26 can be always kept clean.

  Since the heat pump unit 11 includes the heat pump refrigerant circuit X using carbon dioxide as a refrigerant, the temperature of the hot water stored in the hot water supply tank 26 is greatly increased to about 90 ° C. as compared with the refrigerant circuit using the chlorofluorocarbon refrigerant. To rise. According to this, the hot water temperature in the substantially middle part 26C of the hot water supply tank 26 is often maintained at about 50 ° C. If so, the required temperature at the faucet 13 is often about 42 to 43 ° C., so that the hot water in the intermediate portion 26C can be used as it is.

  In the present embodiment, the top hot water discharge pipe 40 is connected to the top 26A of the hot water supply tank 26, and the intermediate hot water supply pipe 33 is connected to the substantially intermediate part 26C between the top 26A and the bottom 26B. , 40 is provided with a mixing valve 100 as a first mixing valve that automatically adjusts by mixing high temperature hot water from the top hot water piping 40 and intermediate hot water from the intermediate hot water piping 33. In addition, the mixing control valve 57 as a second mixing valve for mixing the hot water from the hot water supply pipe 59 and the tap water from the second tap water pipe 62 into the hot water supply pipe 59 on the downstream side of the mixing valve 100. Is provided. For this reason, when the hot water temperature of the intermediate portion 26 </ b> C reaches near the required temperature at the faucet 13, the hot water of the intermediate portion 26 </ b> C can be directly taken out from the faucet 13 through the mixing valve 100.

  When the hot water temperature in the intermediate portion 26C is low, the mixing valve 100 mixes a large amount of hot water from the top portion 26A and sends it to the hot water supply pipe 59. Moreover, when the hot water temperature of the intermediate part 26C is high, the hot water from the top part 26A is sent to the hot water supply pipe 59 with little mixing. When the temperature of hot water passing through the mixing valve 100 is equal to or higher than the hot water temperature at the faucet 13, hot water from the hot water supply pipe 59 and tap water from the second tap water pipe 62 are controlled by opening control of the mixing control valve 57. The temperature of the hot water mixed and fed from the faucet 13 is adjusted to 42 ° C., for example.

  According to this, the hot water in the hot water supply tank 26 can be sent out to the faucet 13 as it is without lowering the temperature with city water such as tap water. Energy efficiency can be improved.

  As the mixing valve 100, for example, a wax valve is used to reduce the cost. On the other hand, an electric valve using a stepping motor or the like is used as the mixing control valve 57, and the mixing accuracy is maintained high.

  As mentioned above, although this invention was demonstrated based on the said one Example, this invention is not limited to this.

FIG. 2 is a circuit diagram showing an embodiment of the heat pump type hot water supply apparatus according to the present invention, in which water in a hot water supply tank is heated and hot water is stored in the tank. In FIG. 1, it is a circuit diagram when supplying hot water to a faucet. In FIG. 1, it is a circuit diagram when pouring into a bathtub. In FIG. 1, it is a circuit diagram when the hot water or water in a bathtub is heated (it chases), and is kept warm.

Explanation of symbols

N Water supply water circulation circuit X Heat pump refrigerant circuit 10 Heat pump type hot water supply device 11 Heat pump unit 12 Hot water supply unit 13 Faucet 14 Bathtub 16 Compressor 19 Refrigerant pipe 26 Hot water supply tank 26A Hot water tank top 26B Hot water tank bottom 26C Middle part of hot water tank 27 Heat exchanger for hot water supply (refrigerant to water heat exchanger)
28 Bath heat exchanger (water-to-water heat exchanger)
33 Intermediate hot water piping 36 Hot water supply water piping 40 Top hot water piping 57 Mixing control valve (second mixing valve)
59 Hot water supply piping 100 Mixing valve (first mixing valve)

Claims (2)

Compressor, heat pump heat exchanger and refrigerant-to-water heat exchanger connected in a loop with refrigerant piping, and a heat pump refrigerant circuit using carbon dioxide as a refrigerant, a hot water tank, a circulation pump, and refrigerant-to-water heat The exchanger is connected in a loop with a hot water supply water pipe, and the water in the bottom of the hot water tank is circulated to the refrigerant-to-water heat exchanger and heated, and the hot water heated by the refrigerant-to-water heat exchanger is heated. A hot water supply water circulation circuit that can be stored in the hot water tank by returning to the top of the tank,
The top hot water supply pipe is connected to the top of the hot water supply tank, the intermediate hot water supply pipe is connected to the intermediate part of the hot water supply tank, and the top hot water supply hot water is connected to the junction of the top hot water supply pipe and the intermediate hot water supply pipe. A first mixing valve for mixing hot hot water from the piping and intermediate hot water from the intermediate outlet piping is provided, and hot water from the hot water supply piping is provided downstream of the first mixing valve in the hot water supply piping. And a second mixing valve for mixing tap water from a tap water pipe.   The heat pump type hot water supply apparatus according to claim 1, wherein the first mixing valve is a wax valve.

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