JPS621647Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a heat pump type water heater, more specifically, a heat exchanger for hot water supply is interposed in the refrigerant circuit of a refrigeration system, and the water in the hot water storage tank is heated using condensation heat in the refrigeration cycle. Regarding a hot water heater that warms the body.

2. Description of the Related Art Conventionally, a heat pump type water heater that uses condensation heat of a refrigeration cycle to generate hot water for hot water supply is already known, as shown in Japanese Utility Model Application Publication No. 53-40570.

As shown in Fig. 1, this water heater has a hot water supply heat exchanger E interposed in a discharge pipe A of a compressor C in a refrigeration system, and a pair of hot water supply heat exchangers E that extend from a hot water storage tank B. The first and second water pipes W ₁ and W ₂ are connected, and a pump P is interposed in the first water pipe W ₁ so that the water sucked from the bottom of the hot water tank B is transferred to the heat exchanger E. The water in the hot water storage tank B is heated and returned to the middle part of the hot water storage tank B, and the water in the hot water storage tank B is heated and hot water is discharged from the hot water supply pipe D.

However, in the water heater configured as described above, when heating the water in the hot water storage tank B, the water passing through the heat exchanger E is heated by heating in the heat exchanger E; The water in B is
Since the temperature rises almost uniformly, it takes a long time for the hot water to reach the hot water temperature, and if a large amount of hot water has been consumed, it is necessary to wait for a long time until the next hot water is poured.

Therefore, to solve the above problems, the second water pipe _W2 is connected to the upper part of the hot water storage tank B, the flow rate of water passing through the heat exchanger E is reduced, and the heat exchanger By increasing the heat transfer area of the heat exchanger E, high temperature hot water can be stored from the upper part of the hot water storage tank B and hot water can be supplied in a short time. ,
Problems arise in that the coefficient of performance of the refrigeration system deteriorates and the heat exchanger E becomes large and uneconomical. On the other hand, the condenser of the refrigeration system is arranged in two parts in parallel, corresponding to the vertical direction of the hot water storage tank and directly under the water of the hot water storage tank, and a solenoid valve is connected to each of these two condensers. For example, a system in which the solenoid valve is switched to flow the refrigerant only to the condenser at the top of the hot water storage tank to intensively heat the water at the top when the water temperature is low has been developed in practical use, for example. Showa 53
It is known from the publication No.-85642. However,
The system described in this publication has two systems on the refrigerant circulation side, so the piping configuration on the refrigerant side is complicated, requiring sophisticated refrigerant connection work at the time of installation, and is extremely difficult to handle. There was a problem. In addition, since the condenser is directly inserted into the water in the hot water storage tank, as the water temperature in the hot water storage tank rises, the condensation temperature also increases, causing high pressure in the refrigerant circuit to rise and reducing efficiency. It was hot because it also happens.

The purpose of this invention is to reduce the amount of water sucked from the bottom of the hot water storage tank and heated by the hot water heat exchanger when the water temperature at the top of the hot water storage tank is low, while being easy to handle and preventing deterioration of operational efficiency. , the water is allowed to flow into the upper part of the hot water storage tank until the temperature of the upper part reaches the set temperature, and then the water is allowed to flow into the bottom of the hot water storage tank without being reduced in volume. To provide hot water at a sufficiently high temperature in a short time without increasing the size of a heat exchanger for use, and to supply a large amount of hot water at a desired temperature.

The configuration of the present invention is that a heat exchanger for hot water supply is interposed in the refrigerant circuit of a refrigeration system, and a first water pipe extending from the bottom of the hot water storage tank and a second water pipe extending from the top are respectively connected to the heat exchanger. A pump is interposed in one of these water pipes, and the water at the bottom of the hot water storage tank is sucked from the first water pipe and passed through the heat exchanger to the second water pipe.
A first circulation path for water returning from the water pipe to the upper part of the hot water storage tank is formed, and a third water pipe extending from the bottom of the hot water storage tank is connected to the middle of the second water pipe that is the discharge side of the pump. to form a second circulation path for drawing water at the bottom of the hot water storage tank from the first water pipe and returning it to the bottom of the hot water tank from the third water pipe via the heat exchanger; The return of hot water heated through the heat exchanger to the hot water storage tank is switched to the second water pipe and the third water pipe depending on the temperature of the water at the upper part of the hot water storage tank, and the water circulation path is changed to the second water pipe and the third water pipe. A selection mechanism for selecting between the first circulation path and the second circulation path is provided, and a restriction is provided in the return system from the second water pipe to the upper part of the hot water storage tank, making it easy to handle. This system is characterized by being able to supply hot water at a high temperature in a short period of time and supply a large amount of hot water at a desired temperature while preventing a decrease in efficiency.

Next, an embodiment of the water heater of the present invention will be described based on FIG.

In FIG. 2, 1 is a compressor 10, an evaporator 1
1. It is a refrigeration system equipped with an expansion valve 12, and a heat exchanger 2 for hot water supply is interposed between the refrigerant circuit, that is, the discharge port of the compressor 10 and the expansion valve 12.

The heat exchanger 2 includes a refrigerant passage 21 connected to a discharge gas pipe 14 of the refrigerant circuit and a liquid pipe 15 leading to the expansion valve 12, a first water pipe 4 extending from the bottom of the hot water storage tank 3, and a first water pipe 4 extending from the top. The refrigerant flowing through the refrigerant passages 21 and the water flowing through the water passage 22 are exchanged with each other as counter-flows to condense the refrigerant and the water is heated.

In addition, a pump 6 is installed in the first water pipe 4 and a throttle 7 is installed in the second water pipe 5. By driving the pump 6, hot water is drawn from the bottom of the storage tank 3, and the water is drawn in from the bottom of the storage tank 3. A first circulation path is formed in which the water is discharged from the second water pipe 5 through the water passage 22 of the heat exchanger 2 through the first water pipe 4 to the upper part of the hot water storage tank 3 at a small flow rate using a throttle 7. The heated water thus discharged collects the hot water in the upper part of the hot water storage tank 3, and the water in the upper part is rapidly heated to a temperature at which hot water can be supplied. By the way, the resistance value of the throttle 7 is set so that the small flow rate value is, for example, 10 to 15% of the optimum amount of water in the heat exchanger 2.

A third water pipe 8 extends from the bottom of the hot water tank 3 between the water passage 21 and the throttle 7 in the second water pipe 5 on the discharge side of the pump 6.
By connecting the third water pipe 8 and the second water pipe 5, the selection mechanism 9 selectively opens the third water pipe 8 and the second water pipe 5.

This selection mechanism 9 uses a three-way valve having one inlet 9a and two outlets 9b and 9c, and this three-way valve is installed in the hot water tank 3 using a thermostat.
The inlet _9a is connected to the water passage 21 in the second water pipe 5 _, and the outlet 9b is connected to the throttle 7. The end of the third water pipe 8 is connected to the outlet 9c of the three-way valve. On the other hand, the water temperature sensing part th ₁₁ is installed at an intermediate position above and below the hot water tank 3, and the water temperature around the water temperature sensing part th ₁₁ is adjusted to the temperature of the thermostat th ₁ by the water temperature sensing part th ₁₁ . When the water temperature is lower than the set temperature, the inlet 9a and outlet 9b of the three-way valve are selectively opened to open the second water pipe 5 of the first circulation path, and when the water temperature reaches the set temperature, the three-way valve is opened. selectively open between the inlet 9a and outlet 9c,
When the pump 6 is driven, hot water is sucked from the bottom of the storage tank 3, flows into the water passage 22 of the heat exchanger 2, and flows from the middle of the second water pipe 5 to the third water pipe 8.
A second circulation path is formed through which water is discharged to the bottom of the hot water storage tank 3 to heat the water below the hot water storage tank. The compressor 10 is installed below the hot water storage tank when the water temperature below reaches a desired temperature.
A temperature sensing element _th22 of the thermostat _th2 is provided to stop the operation.

In addition, in FIG. 2, 31 is a water supply pipe, and 32 is a hot water outlet pipe.

The water heater of the present invention is constructed as described above, and when heating the water in the hot water storage tank 3, it is heated by driving the compressor 10 of the refrigeration device 1 and also driving the pump 6. , the first circulation path and the second circulation path are selectively opened by the water temperature sensing section _th1 , and the water in the hot water storage tank 3 circulates between it and the heat exchanger 2.

Therefore, the water is circulated through the first circulation path by sucking a small amount of water from the bottom of the hot water storage tank 3 through the throttle 7 and flowing into the inlet of the water passage 22 opposite to the outlet of the refrigerant passage 21 in the heat exchanger 2. After being heated by the latent heat of condensation of the refrigerant, it is heated by the sensible heat of condensation of the discharged gas refrigerant, and is discharged to the upper part of the hot water storage tank 3, thereby intensively heating the water in the upper part.

Therefore, the water temperature in the upper part of the hot water storage tank 3 can be raised more rapidly than in the case where the entire water temperature is raised averagely, and hot water can be supplied at a high temperature in a short time.

When the water temperature in the upper part of the hot water tank 3 reaches the set temperature, the water in the lower part of the hot water tank 3 circulates through the first circulation path, and this circulation starts from the bottom of the hot water tank 3 through the heat exchanger. 2, the optimum amount of water is sucked in, flows through the water passage 22 of the heat exchanger 2, is heated by the condensation heat of the refrigerant, and is discharged to the bottom of the hot water storage tank 3, discharging a large amount of water in the hot water storage tank 3. It can be heated to the desired temperature.

By the way, the set temperature of the temperature sensing part th ₁₁ is set to 45℃
By setting the temperature at 65°C, the water temperature in the upper part of the hot water storage tank 3 can be rapidly heated from 45°C to 65°C, and a large amount of water below the heated part can also be heated to the desired temperature.

As described above, when heating the water temperature in the upper part of the hot water storage tank 3 to the set temperature, the heating time can be extremely short compared to the entire heating time, and after heating the upper part of the hot water storage tank 3, the water temperature in the lower part is heated. Since the optimum flow rate can be passed through the heat exchanger 2 after the upper part is heated, the refrigeration system 1 can be operated without reducing the bulk coefficient of the refrigeration system 1 as a whole. Moreover,
After the upper part is heated, heated water is discharged to the bottom of the hot water storage tank 3, so the high temperature water that accumulates in the upper part is not stirred by the discharged heated water and lowered in temperature, and is stably maintained at the set temperature. It is.

By the way, the above explanation is for the case of full water addition operation in which the upper part of the hot water storage tank 3 is heated to the set temperature and then the lower part is heated. After heating the upper part of the hot water storage tank 3 to a set temperature, the operation can be switched to the upper water heating operation where the operation is immediately stopped.

That is, between the power supply line, the lower thermostat _TH2 and the electromagnetic switch MS of the motor MC of the compressor 10 are connected.
a first series circuit with the upper thermostat;
a second series circuit between th ₁ and the three-way valve 9; a third series circuit between the normally open contact MSa of the electromagnetic switch MS and the motor MC of the compressor 10; and a third series circuit between the electromagnetic switch MS and the motor MC of the compressor 10.
The fourth contact MSa between the normally open contact MSa and the fan motor MF
a series circuit, and a fifth series circuit of the normally open contact MSa of the electromagnetic switch MS and the motor MP of the pump 6,
A changeover switch _SW1 is provided in the first series circuit, and the changeover switch SW1 is connected in parallel with each other and can manually switch the continuity between the terminals _{t1 and t2} and the terminals t1 _{and t3} . One of the switching terminals t ₂ and t ₃ , t _2, is connected to the power source, and the other t ₃ is connected to the contact of the upper thermostat th ₁ , which closes when the temperature is low. By the way, the three-way valve 9 opens between the inlet 9a and the outlet 9b when energized, and opens between the inlet 9a and the outlet 9 when not energized.
A three-way solenoid valve is used that switches as if the gap between c and c is opened.

Note that CB is an earth leakage breaker and SW ₂ is a power switch.

In the above configuration, the upper part of the hot water tank ₃ is heated to the temperature set by the thermostat th 1 by operating the changeover switch SW ₁ so that the terminals t ₁ and t ₂ are electrically connected as shown in FIG. After that, the lower part is heated to the set temperature of thermostat th ₂ , and the operation is stopped by de-energizing the electromagnetic _{switch MS} . , t ₂ conducts, and when the upper part of the hot water storage tank 3 is heated to the set temperature of the thermostat th ₁ , the thermostat th ₁ opens and the operation is immediately stopped. This allows for warm operation.

Therefore, if you only want a small amount of high-temperature water, you can stop the operation in a short time by doing the latter operation, and if you want a large amount of high-temperature water, you can do the former operation. , high-temperature water can be obtained in a short time, and a large amount of high-temperature water can also be obtained. Furthermore, all of these operations do not require any operation during operation, and can be selected by simply operating changeover switch SW ₁ in advance, allowing you to supply the necessary hot water without any effort. , wasteful operation can be prevented, and overall hot water supply costs can be reduced.

Note that the three-way solenoid valve 9 is disconnected from the inlet 9 due to non-conduction.
A, the outlet 9b is opened, and the inlet 9a is opened by energization.
The switch may be made so that the outlet 9c is opened, and in this case, as shown in _FIG . Said changeover switch SW ₁
The other of the switching terminals t ₂ and t ₃ t ₃ is connected, and the three-way solenoid valve 9 is connected in series to the contact that closes when the temperature is high.

Further, in the above description, the pump 6 is provided in the first water pipe 4, but it may be provided in the second water pipe 5 between the inlet 9a of the three-way valve and the water passage 22.

Furthermore, in the above description, a three-way valve was used as the selection mechanism 9, but two two-way valves may also be used. That is, the end of the third water pipe 8 is connected to the second water pipe 5 between the throttle 7 and the water passage 22, and the second water pipe 5 on the hot water storage tank 3 side at this connection point and the third water pipe 8
A two-way valve may be provided for each of the water pipes 5 and 8, and the water temperature heating portion _th11 may be used to selectively open the water pipes.

Further, the aperture 7 may be a capillary reach tube, or may be provided inside a two-way valve or a three-way valve.

As described above, according to the present invention, when the water temperature in the upper part of the hot water storage tank 3 is low, the selection means 9 selects the first
By selecting a water circulation path and circulating the water at the bottom of the hot water tank 3 through the heat exchanger 2 and through the throttle 7 to the upper part of the hot water storage tank 3, The water temperature in the upper part can be raised rapidly, and hot water can be supplied at a sufficiently high temperature in a short period of time even when starting up or when a large amount of hot water is consumed.

Further, when the water temperature in the upper part of the hot water storage tank 3 increases due to the circulation through the first circulation path, the second circulation path is selected by the selection means 9, and the water in the bottom part of the hot water storage tank 3 is transferred to the heat exchanger 2. After that, the amount of water is increased to the original optimum amount without passing through the throttle 7 through the third water circulation path 8, and is circulated to the bottom of the hot water storage tank 3, thereby stirring the high temperature water at the top of the hot water storage tank 3. While the temperature can be stably maintained at the set temperature without any problems, the high temperature water in the upper part of the hot water storage tank 3 can be heated and the low temperature water in the lower part can be heated, and a large amount of hot water can be supplied at the desired temperature.

Moreover, in order to rapidly raise the temperature of the water in the upper part of the hot water storage tank 3, the water circulation side is
Because it has a two-system configuration of the water circulation path, in other words,
Since the refrigerant circulation side, that is, the condenser side, is not composed of two systems at all, there are problems that arise when dividing the refrigerant circulation side into two systems, namely, the refrigerant piping configuration becomes complicated and it is difficult to connect the refrigerant at the time of equipment installation. Problems that would have made the work cumbersome did not occur at all, and the handling became easy.

Furthermore, in order to rapidly raise the temperature of the water in the upper part of the hot water storage tank 3, the hot water storage tank 3 and the heat exchanger 2
Since the water flowing through the water pipes 4 and 5 is connected to the heat exchanger 2 through the water pipes 4 and 5, and the heat exchanger 2 is connected to the heat exchanger 2, in other words, the refrigerant side condenser is directly Since the condenser is not inserted into the water in the hot water tank at all, there is a problem that occurs when the condenser is directly inserted into the water in the hot water storage tank, namely, the condensation temperature increases as the water temperature in the hot water storage tank increases. This eliminates the problem of a drop in efficiency due to an increase in the high pressure in the refrigeration system, and overall efficient hot water supply operation has been achieved.

Moreover, as described above, when heating the upper water temperature of the hot water storage tank 3 to the set temperature and the lower water temperature of the upper water to the desired temperature, the time occupied by the upper heating in the entire heating time is small, and the lower heating In this case, the optimal flow rate can be passed through the heat exchanger, so the bulk coefficient of the refrigeration system 1 does not decrease, and there is no need to make the heat exchanger 2 large.

[Brief explanation of the drawing]

Fig. 1 is a piping system diagram showing a conventional example, Fig. 2 is a piping system diagram showing an embodiment of the present invention, Figs.
The figure is an electrical circuit diagram. 1... Refrigeration device, 2... Heat exchanger for hot water supply, 3...
... Hot water tank, 4... First water pipe, 5... Second water pipe, 6... Pump, 7... Throttle, 8... Third water pipe, 9... Selection mechanism.

Claims (1)

[Scope of utility model registration request] A hot water supply heat exchanger 2 is interposed in the refrigerant circuit of the refrigeration device 1, and a first water pipe 4 extending from the bottom of the hot water storage tank 3 and a second water pipe 5 extending from the top are connected to the heat exchanger 2, respectively. A pump 6 is interposed in one of these water pipes 4 and 5, and the water at the bottom of the hot water tank 3 is sucked from the first water pipe 4, passes through the heat exchanger 2, and is transferred to the second water pipe 5. In the middle of the second water pipe 5, which forms a first circulation path for returning water from the water to the upper part of the hot water storage tank 3, and which becomes the discharge side of the pump 6,
A third water pipe 8 extending from the bottom of the hot water tank 3 is connected to draw water from the bottom of the hot water tank 3 through the first water pipe 4 and from the third water pipe 8 through the heat exchanger 2. A second circulation path for water to be returned to the bottom of the hot water storage tank 3 is formed, while a second circulation path for returning hot water heated through the heat exchanger 2 to the hot water storage tank 3 is formed.
is provided with a selection mechanism 9 that switches between the second water pipe 5 and the third water pipe 8 and selects the water circulation path between the first circulation path and the second circulation path according to the temperature of the upper water, and , A heat pump water heater characterized in that a throttle 7 is provided in a return system from the second water pipe 5 to the upper part of the hot water storage tank 3.