JP5982635B2 - Heat pump water heater - Google Patents

Description

  The present invention relates to a heat pump water heater.

  Conventionally, this type of hot water supply apparatus has a function of storing heat of the incoming pipe at the outlet of the hot water tank (see, for example, Patent Document 1).

  FIG. 4 shows a conventional hot water supply apparatus described in Patent Document 1. As shown in FIG.

  As shown in FIG. 4, the hot water supply apparatus 100 includes a hot water storage tank 101, a heat pump unit 102, a heating unit 103, a heat storage unit 104, a heat exchange unit 107, and a heat medium circulation path 108. The heat storage unit 104 is disposed so as to contact both the water inlet pipe 105 from the hot water storage tank 101 to the heat pump unit 102 and the water supply pipe 106 from the external water supply to the hot water storage tank 101.

  With this configuration, the intermediate temperature intermediate temperature water sent from the hot water storage 101 to the heat pump unit 102 is deprived of heat by the heat storage unit 104 and the water temperature is lowered.

  Further, the heat taken into the heat storage unit 104 raises the temperature of the makeup water through the feed water pipe 106 when the makeup water from the outside is supplied to the hot water storage tank 101.

  As a result, in the heat pump unit 102, the heating temperature difference between the refrigerant and water is increased to increase the heat exchange efficiency of the heat pump unit 102.

JP 2011-7418 A

  However, in the conventional configuration, makeup water supplied to the hot water storage tank 101 absorbs heat from the heat storage unit 104 through the water supply pipe 106 and then flows into the hot water storage tank 101. The water in the hot water storage tank 101 into which the makeup water has flowed passes through the water intake pipe 105 and is absorbed by the heat storage unit 104.

  Therefore, since the heat storage unit 104 absorbs again the heat released to the makeup water through the water supply pipe 106 through the water intake pipe 105, the stored heat energy cannot be used effectively, and energy efficiency is reduced. Had problems.

  The present invention solves the above-mentioned conventional problems, by reducing the incoming temperature of water supplied to the heat pump unit, improving the heat exchange efficiency of the heat pump, and using the stored thermal energy, An object of the present invention is to provide a heat pump hot water supply device that reduces the amount of boiling water and has high energy efficiency.

In order to solve the conventional problems, a heat pump hot water supply apparatus of the present invention includes a heat pump unit, a hot water storage tank for storing hot water heated by the heat pump unit, and an inlet pipe for supplying water from the hot water storage tank to the heat pump unit. A boiling pipe for sending hot water heated by the heat pump unit to the hot water storage tank, a hot water supply pipe for discharging hot water from the hot water storage tank, a water supply pipe for supplying water to the hot water storage tank, and a branch from the water supply pipe And a bypass pipe connected to the outlet pipe, and a heat storage unit for transferring heat between the inlet pipe and the bypass pipe is connected to each of the inlet pipe and the bypass pipe via a joint. It is connected, and the entering water pipe, each pipe of the bypass pipe, especially that on-off valve and the drain plug is provided It is an.

This reduces the incoming temperature of the water supplied to the heat pump unit by absorbing heat in the heat storage unit, improves the heat exchange efficiency of the heat pump unit, and joins the hot water piping using the heat energy of the heat storage unit By heating water, the amount of boiling water can be reduced and energy efficiency can be improved.

  The present invention can provide a heat pump hot water supply apparatus that is excellent in energy efficiency.

The block diagram of the heat pump hot-water supply apparatus in Embodiment 1 of this invention Detailed view around the heat storage unit The block diagram of the heat pump hot-water supply apparatus in Embodiment 2 of this invention Configuration diagram of conventional hot water supply equipment

The first invention includes a heat pump unit, a hot water storage tank for storing hot water heated by the heat pump unit, an inlet pipe for supplying water from the hot water storage tank to the heat pump unit, and hot water heated by the heat pump unit. A boiling pipe for sending to the hot water tank, a hot water pipe for discharging hot water from the hot water tank, a water supply pipe for supplying water to the hot water tank, and a bypass pipe branched from the water supply pipe and connected to the hot water pipe A heat storage unit for transferring heat between the water inlet pipe and the bypass pipe is connected to each pipe of the water inlet pipe and the bypass pipe via a joint, and the water inlet pipe, Each of the bypass pipes is provided with an open / close valve and a drain plug .

  This reduces the incoming temperature of the water supplied to the heat pump unit by absorbing heat in the heat storage unit, improves the heat exchange efficiency of the heat pump unit, and joins the hot water piping using the heat energy of the heat storage unit By heating water, the amount of boiling water can be reduced and energy efficiency can be improved.

In particular, the second invention includes a boiling pump disposed on a path of the water inlet pipe, supplying water to the heat pump unit, and including the drain plug , in the first invention, The pump is a heat pump hot water supply device, wherein the pump is disposed at a lowest position on a pipe route of the water inlet pipe.

  Thereby, when performing maintenance, such as replacement | exchange of a thermal storage unit, hot water can be extracted from the drain plug of a boiling pump. Therefore, it is possible to remove hot water from the heat storage unit by installing only one drain plug in the pipe that is not connected to the boiling pump among the pipes that connect the heat storage unit. Cost reduction can be realized.

  A third invention is a heat pump hot water supply apparatus according to the first or second invention, wherein the heat storage unit is filled with a latent heat storage material.

  Thereby, when the temperature of incoming water entering the heat pump unit is high, heat can be radiated to the heat storage material, and low-temperature and constant-temperature water can be continuously supplied to the heat pump unit.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1 is a configuration diagram of a heat pump hot water supply apparatus according to Embodiment 1 of the present invention, and FIG. 2 is a detailed view of the vicinity of a heat storage unit according to Embodiment 1 of the present invention.

  In FIG. 1, a heat pump hot water supply apparatus in the present embodiment includes a hot water storage tank 1, a heat pump unit 2 as a heating means for heating water in the hot water storage tank 1, a heat storage unit 4, a heating unit 10, and a heating unit 10. The heat exchanger 11 is configured to exchange heat between the water and the water in the hot water tank 1.

  The water in the hot water tank 1 is heated by the heat pump unit 2 through the first on-off valve 26, the incoming water pipe 5, the heat storage unit 4, and the boiling pump 12 disposed on the incoming water pipe 5. It passes through the pipe 13 and flows into the hot water tank 1.

  The boiling pump 12 is installed at the lowest position of the incoming water pipe 5.

  The first on-off valve 26 is closed when maintenance such as replacement of the heat storage unit 4 is performed, and is normally kept open.

  A water supply pipe 14 in the lower part of the hot water tank 1 is connected to a water supply pipe 6 such as a water pipe through a pressure reducing valve 15. A hot water supply pipe 16 at the upper part of the hot water tank 1 is connected to a hot water supply pipe 18 via a mixing valve 17. The bypass pipe 19 branched from the water supply pipe 14 is connected to the mixing valve 17 via the second on-off valve 27 and the heat storage unit 4.

  The second on-off valve 27 is closed when maintenance such as replacement of the heat storage unit 4 is performed, and is normally kept open.

  The heating forward pipe 20 at the upper part of the hot water tank 1 is connected to the heating return pipe 22 of the hot water tank 1 through the heat exchanger 11 and the heating primary pump 21. The outlet pipe 23 of the heating unit 10 has a heating secondary pump 24 on the pipe path, and is connected to the inlet pipe 25 of the heating unit 10 via the heat exchanger 11.

  About the hot water supply apparatus comprised as mentioned above, the operation | movement and an effect | action are demonstrated below.

  As a basic operation in the use of hot water in a general home, hot water for the day is stored in the hot water tank 1 in the morning, and is sequentially used for hot water supply during an active time. When the amount of hot water storage is insufficient during use of hot water, the heat pump unit 2 may be operated as necessary, and an additional hot water storage operation may be performed.

  First, hot water storage operation will be described. The water in the hot water storage tank 1 passes through the first on-off valve 26, the water inlet pipe 5, and the heat storage unit 4 and is led to the boiling pump 12. For example, in the case where the heat storage unit 4 is filled with a latent heat storage material having a melting point of 10 to 20 ° C., the water in the hot water tank 1 at about 30 ° C. is cooled to about 20 ° C. and guided to the boiling pump 12. The heat pump unit 2 is heated to about 65 to 90 ° C., passes through the boiling pipe 13 and flows into the hot water tank 1 to perform a hot water storage operation.

  Therefore, when medium-temperature water of about 30 ° C is in the hot water storage tank and the boiling operation is performed by the heat pump unit, first, the medium-temperature water of about 30 ° C enters the heat storage unit, and the heat storage unit absorbs the heat of the medium-temperature water. After the temperature of the hot water is lowered, it flows into the heat pump unit 2 and a boiling operation is performed. Thereby, the heating temperature difference in the heat pump unit 2 can be further increased, and the heat exchange efficiency can be improved.

Next, the heating operation will be described. When the heating operation command is issued, the heating primary pump 21 is activated. Thereafter, the heating secondary pump 24 is activated, heat is exchanged in the heat exchanger 11, and the heating unit 10 is warmed to about 30 ° C. At this time, the water in the heating return pipe 22 downstream of the heating primary pump 21 reaches about 35 ° C. and returns to the hot water tank 1. If this heating operation is continued, the hot water in the hot water tank 1 decreases, so the hot water storage operation by the heat pump unit 2 described above is performed.

  At this time, the temperature at the bottom of the hot water tank 1 is medium temperature water of about 35 ° C. Here, similarly to the hot water storage operation described above, if the heat storage unit 4 is filled with a latent heat storage material having a melting point of 10 to 20 ° C., the medium temperature water of the hot water storage tank 1 having a temperature of about 35 ° C. passes through the inlet pipe 5. Then, after being cooled to about 20 ° C., it is led to the boiling pump 12, flows into the heat pump unit 2, is heated to 65-90 ° C., flows into the hot water tank 1 through the boiling pipe 13.

  Therefore, when medium temperature water of about 35 ° C. returns to the hot water tank and then the boiling operation is performed by the heat pump unit, first, the medium temperature water of about 35 ° C. enters the heat storage unit and is lowered to about 20 ° C. Since it enters the unit and performs a boiling operation, the heating temperature difference in the heat pump unit can be increased, and the heat exchange efficiency can be increased.

  Next, the hot water supply operation will be described. When a user opens a faucet (not shown) downstream of the hot water supply pipe 18, the hot water from the hot water discharge pipe 16 and the water from the bypass pipe 19 at the upper part of the hot water tank 1 are brought to a desired temperature by the mixing valve 17. It is mixed and hot water is supplied. Here, when heat is stored in the heat storage unit 4 in the heating operation described above, the low temperature water of about 9 ° C. is heated to about 15 ° C. through the heat storage unit 4 in the water supply pipe 6 and is bypassed. 19 is led to the mixing valve 17.

  In this way, the heat energy stored in the heat storage unit 4 is used to increase the temperature of the water passing through the bypass pipe 19, so that the amount of hot water from the hot water tank 1 necessary to achieve a desired hot water supply temperature can be reduced. it can. That is, since the amount of hot water to be boiled can be reduced, the efficiency of the heat pump hot water supply apparatus can be improved.

  As described above, in the present embodiment, the temperature of water flowing into the bypass pipe is increased by reducing the temperature of water entering the heat pump unit to increase the heat exchange efficiency of the heat pump unit and storing the heat energy. Since the amount of hot water used from the hot water tank to achieve the desired hot water supply temperature can be reduced, that is, the amount of boiling water can be reduced, the energy efficiency of the heat pump hot water supply device can be improved.

  In addition, since the heat storage unit 4 is filled with a latent heat storage material having a melting point of 10 to 20 ° C., there is a temperature difference between the heat storage material and tap water when the heat energy stored in the latent heat storage material is lost. Get smaller. Therefore, since the transitional change of the outlet temperature of the heat storage unit 4 can be reduced, the fluctuation of the hot water supply temperature via the mixing valve 17 can be reduced.

  In addition, in this Embodiment, although the case where the heating unit 10 was connected as a heat pump hot-water supply apparatus was demonstrated, even if the bathtub is connected instead of the heating unit 10, the same effect can be acquired.

  Moreover, although this embodiment demonstrated the case where the heat storage unit 4 was filled with a latent heat storage material having a melting point of 10 to 20 ° C., the melting point was 20 to 30 ° C. depending on the temperature of water supplied to the hot water tank. The latent heat storage material may be used.

  In the present embodiment, the case where one kind of latent heat storage material is filled in the heat storage unit 4 has been described, but a plurality of latent heat storage materials having different melting points may be used.

In the present embodiment, the refrigerant sealed in the heat pump unit 2 is not particularly mentioned, but a refrigerant such as carbon dioxide, R410A or HC refrigerant may be used.

  Next, the details of the peripheral structure of the heat storage unit 4 and the boiling pump 12 will be described.

  In FIG. 2, the heat storage unit 4 is installed above the boiling pump 12 in the gravity direction, and a first drain plug 28 is attached to the lower part of the boiling pump 12. A second drain plug 29 is attached to the lowermost side of the bypass pipe 19 in the gravity direction. Further, the water inlet pipe 5 and the bypass pipe 19 are connected to the first on-off valve 26 and the second on-off valve 27 by a joint 30, respectively, and the joints 30 are also connected to each other.

  Generally, when performing maintenance such as replacement of the heat storage unit 4, it is necessary to remove hot water from the heat storage unit 4, and two drain plugs are required below the heat storage unit 4. However, since the boiling pump is installed at the lowest position of the incoming water pipe, hot water can be extracted from the drain plug of the boiling pump 12. Therefore, the hot water in the heat storage unit 4 can be drawn out by installing only one drain plug in the pipe that is not connected to the boiling pump 12 among the pipes that communicate with the heat storage unit. Costs can be reduced in the manufacture of the device.

(Embodiment 2)
FIG. 3 is a diagram showing a configuration of a heat pump hot water supply apparatus according to Embodiment 2 of the present invention.

  In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 3, the outlet pipe 23 of the heating unit 10 has a heating secondary pump 24 on the pipe path, and an inlet pipe 25 of the heating unit 10 via a heat exchanger 31 installed in the hot water tank 1. It is connected to the.

  Next, the heating operation will be described. When a heating operation command is issued, the heating secondary pump 24 is activated, heat exchange is performed by the heat exchanger 31 installed in the hot water tank 1, and the heating unit 10 is heated to about 30 ° C.

  On the other hand, the temperature of the hot water in the hot water storage tank 1 is lowered by the water that is discharged from the heating unit 10 performing heat exchange in the heat exchanger 31 installed in the hot water storage tank 1. When this heating operation is continued, the hot water in the hot water tank 1 is reduced, and it is necessary to perform the hot water storage operation by the heat pump unit 2. At this time, since the temperature of the inner bottom of the hot water tank 1 is medium temperature water of about 35 ° C., the water is heated by the heat pump unit 2.

  Here, for example, when the heat storage unit 4 is filled with a latent heat storage material having a melting point of 10 to 20 ° C., the medium temperature water from the hot water tank 1 passes through the heat storage unit 4 and is boiled after being cooled to about 20 ° C. It is guided to the pump 12, heated to 65 to 90 ° C. by the heat pump unit 2, and flows into the hot water tank 1 through the boiling pipe 13.

  Thus, the heat storage unit 4 can reduce the incoming water temperature entering the heat pump unit 2, so that the heat exchange efficiency of the heat pump unit 2 can be increased.

  Moreover, since the heat exchanger 31 is installed inside the hot water tank 1, heat exchange between the fluid inside the hot water tank 1 and the fluid used in the heating unit 10 can be performed with a simple configuration.

  As described above, the hot water supply apparatus according to the present invention can improve the efficiency of the system by storing heat in a hot water storage tank by a plurality of heat sources, and therefore can be applied to a hot water supply apparatus for home use and a scale for business use. It can also be applied to hot water heaters with large size.

DESCRIPTION OF SYMBOLS 1 Hot water storage tank 2 Heat pump unit 4 Thermal storage unit 5 Intake piping 12 Boiling pump 13 Boiling piping 14 Water supply piping 16 Hot water piping 19 Bypass piping

Claims (3)

A heat pump unit, a hot water storage tank for storing hot water heated by the heat pump unit, a water inlet pipe for supplying water from the hot water storage tank to the heat pump unit, and boiling water for sending hot water heated by the heat pump unit to the hot water storage tank A water supply pipe for supplying hot water from the hot water storage tank, a water supply pipe for supplying water to the hot water storage tank, and a bypass pipe branched from the water supply pipe and connected to the hot water supply pipe. And a heat storage unit that transfers heat between the bypass pipe and the bypass pipe are connected to the respective pipes of the inlet pipe and the bypass pipe via joints, and each of the inlet pipe and the bypass pipe A heat pump hot water supply apparatus , wherein the pipe is provided with an on-off valve and a drain plug . The heating pump unit is provided on a path of the water inlet pipe, supplies water to the heat pump unit, and includes a boiling pump including the drain plug. The boiling pump is the lowest on the pipe path of the water inlet pipe. The heat pump hot water supply apparatus according to claim 1, wherein the heat pump hot water supply apparatus is disposed at a position. The heat pump hot water supply apparatus according to claim 1 or 2, wherein the heat storage unit is filled with a latent heat storage material.