JPS6256415B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water heater that supplies hot water using a refrigeration device that uses air as a heat source.

When hot water is supplied using this type of water heater, heating operation is performed throughout the year, so the capacity becomes extremely large when the outside temperature is high, such as in the summer. On the other hand, when the outside temperature is low, such as in winter, the capacity becomes low. At this time, since the amount of water circulating between the heat pump device and the hot water storage tank is constant, the capacity is determined by the difference between the inlet water temperature and outlet water temperature of the heat exchanger on the user side. In other words, when the outside temperature is high, the difference in water temperature at the entrance and exit is large;
If it is low, it will be small. When controlling the operation of such a heat pump water heater using a thermostat installed on the inlet water temperature side, if the hot water supply temperature is set to 55°C, for example, and the set temperature of the thermostat is set to 52°C, for example, based on the low outside temperature, During high outside temperatures such as in summer, the outlet water temperature becomes high, for example 62℃, and the high pressure rises to, for example, 30Kg/cm ² .
The safety device's high-pressure switch, set at 28Kg/ ^cm2 , was activated, resulting in an abnormal shutdown. On the other hand, if the temperature setting of the thermostat is set to, for example, 45 degrees Celsius based on the high outside temperature, the thermostat will operate before the outlet water temperature reaches, for example, 55 degrees Celsius during low outside temperatures such as in winter, and the outlet water temperature will rise to, for example, 55 degrees Celsius. There was a drawback that the operation stopped at 48℃.

This invention was made to eliminate the above-mentioned drawbacks, and one embodiment of the invention will be described below. In Fig. 1, 1 is a hot water storage tank whose surroundings are insulated, 1a is a hot water supply port from hot water storage tank 1, 1b is a supply water pipe to hot water storage tank 1, and 2 is a heat pump device, which is a compressor that forms a heat pump cycle. 2
a, a four-way switching valve 2b, a heat source side heat exchanger 2c that exchanges heat between the low-pressure refrigerant and air during hot water supply operation, a manifold check valve 2d, an expansion device 2e, and a high-pressure refrigerant flowing through the inner pipe and the inside and outside during hot water supply operation. It has a double pipe type user side heat exchanger 2f that exchanges heat with water flowing between the pipes. 3 and 4 are an outgoing pipe and a return pipe, 5 is a circulation pump that is installed in the return pipe 4 and circulates hot water, and 6a and 6b are the inlet and outlet sides of the water circuit of the user heat exchanger, the outgoing pipe 3, and the return pipe. tube 4
The inlet piping and outlet piping connect these piping connections to form a circulation circuit. 7 is a first set temperature provided in the inlet pipe 6a, for example
A first temperature sensor 8 is also a second temperature sensor for detecting the inlet water temperature which operates at 52°C, and has a second set temperature lower than the first temperature sensor 7, for example 45°C.
It operates with. Reference numeral 9 denotes an outside temperature detector that detects the suction temperature of the heat source side heat exchanger 2c. Also, Figure 2 shows
An electrical circuit diagram of the main parts showing one embodiment of this invention,
5a is a pump electromagnetic contactor for operating the circulation pump 5, 7a is a b contact of the first temperature detector 7, 8a is a b contact of the second temperature detector 8, and 9a is a contact piece of the outside temperature detector 9. For example, when the temperature rises above 20°C, the contact changes from the "low" contact side to the "high" contact side. 10
1 is a compressor electromagnetic contactor for operating the compressor 2a of the heat pump device 2, and 11 is an operation switch. Further, the b contact 7a of the first temperature sensor 7 is on the "low" contact side of the contact piece 9a of the outside temperature sensor 9, and the second temperature sensor 8 is on the "high" contact side of the contact piece 9a. b of
The contact 8a is connected to constitute a switching circuit 12 for the first and second temperature detectors 7 and 8. A compressor electromagnetic contactor 10 is connected in series with this switching circuit 12.
are connected, and furthermore, a pump electromagnetic contactor 5a is connected in parallel with these. In such a configuration, when the outside temperature is 0° C., which is lower than the set temperature of the outside temperature detector 9, for example, 20° C., such as in winter, the contact piece 9a is exemplified as a “low” contact side. .
When the operation switch 11 is closed at this time, the circulation pump 5 is activated by the excitation of the pump electromagnetic contactor 5a, and the b contact 7a of the first temperature sensor 7 is activated.
The compressor electromagnetic contactor is energized through the compressor, the compressor 2a is operated, and the refrigerant is circulated as shown by the solid arrow in FIG. 1 to perform hot water supply operation. When the water temperature reaches the set temperature of the first temperature detector 7, for example 52° C. or higher, the b contact 7a is opened and the compressor 2a is stopped. On the other hand, in summer, etc., the outside temperature is 30°C higher than the set temperature of the outside temperature detector 9, for example 20°C.
In this case, the contact piece 9a will fall to the "high" contact side,
Thereafter, the compressor electromagnetic contactor 10 is energized only through the b contact 8a of the second temperature detector 8, and the operation is the same as in winter. In this way, when the outside temperature is low, the capacity of the heat pump device 2 is small, and the temperature difference between the entrance and exit of the user-side heat exchanger 2f, for example,
Although the compressor 2a is small at 3deg, the compressor 2a can continue operating up to the relatively high set temperature of the first temperature detector 7, for example, 52°C, and raise the outlet water temperature of the user-side heat exchanger 2f to, for example, 55°C. . In addition, when the outside temperature is high, the capacity of the heat pump device 2 is large,
For example, the temperature difference between the inlet and outlet of the heat exchanger 2f on the user side is
Although the temperature is increased to 10 degrees, the operation of the compressor 2a is stopped at a relatively low set temperature of the second temperature detector 8, for example, 45 degrees Celsius, and the outlet water temperature of the user side heat exchanger 2f is suppressed to, for example, 55 degrees Celsius. Therefore, the high pressure of the heat pump device 2 is, for example, about 25 kg/cm ² and does not become abnormally high, and the heat pump device 2 does not stop abnormally. In such an operating state, the circulation pump 5 circulates between the hot water tank 1 and the user-side heat exchanger 2f.
The water is circulated between the
Store hot water at 55℃. Then, this hot water is appropriately supplied to the outside from the hot water supply port 1a. If frost forms on the heat source side exchanger 2c due to hot water supply operation at low outside temperatures, the four-way switching valve 2b and manifold check valve 2d are switched to circulate the refrigerant as shown by the dotted line arrow in Fig. 1 to remove frost. A frost operation is performed, but since the defrosting time is short, there is no practical problem in hot water supply. Note that a normal refrigeration device may be used instead of the heat pump device 2, and in this case, the defrosting of the heat exchanger on the heat source side is performed by an electric heater or a hot gas bypass circuit that directly supplies discharge gas from the compressor. You can do it by leaning.

As described above, in this invention, when the outside temperature is low, the first temperature detector operates the refrigeration system to supply hot water until the inlet water temperature of the user-side heat exchanger is relatively high.
When the outside temperature is high, the second temperature detector is used to stop the hot water supply operation of the refrigeration system when the inlet water temperature of the heat exchanger on the user side is relatively low, so high temperature water can be obtained even when the outside temperature is low. Furthermore, when the outside temperature is high, the high pressure of the refrigeration system will not rise abnormally and the refrigeration system will not stop abnormally.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an embodiment of the present invention, and FIG. 2 is an electrical circuit diagram of the same essential parts. In the figure, 1 is a hot water storage tank, 2 is a heat pump device, 2c is a heat source side heat exchanger, 2f is a user side heat exchanger, 3 and 4 are outgoing pipes and return pipes, 7 and 8 are first and second 2 is a temperature detector, and 9 is an outside temperature detector.

Claims (1)

[Claims] 1 A refrigeration system having a hot water storage tank for hot water supply, a heat source side heat exchanger for exchanging heat between low pressure refrigerant and air during hot water supply operation, and a user side heat exchanger for exchanging heat between high pressure refrigerant and water during hot water supply operation; A circulation circuit that connects a heat exchanger on the user side of the device and the hot water storage tank for water supply and circulates water between the two, detects the water temperature on the inlet side of the heat exchanger on the user side of the refrigeration device,
a first temperature detector that operates at a first set temperature; a second temperature sensor that detects the water temperature at the inlet side of the refrigeration system and operates at a second set temperature that is lower than the first temperature detector; , and when the outside air temperature is lower than a predetermined temperature, the first temperature sensor controls the hot water supply operation of the refrigeration system, and when the outside air temperature is higher than the predetermined temperature, the second temperature sensor starts the hot water supply operation of the refrigeration system. A water heater equipped with a control circuit that controls.