JPH0139023B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water heater that stores hot water using late-night electricity or the like and is equipped with an economical auxiliary heating device in addition to the heating device in the hot water storage tank.

In conventional electric water heaters equipped with heat pump heat source equipment, for example, the hot water in the hot water storage tank is used by the user at will, and depending on changes in daily living patterns, the amount of hot water used may be extremely small. . On the other hand, the return water temperature detection sensor 13 is used to determine whether or not the heat pump can be operated, but this sensor 13 is provided inside the outer case 18 and is provided in a narrow place such as the circulation path 6 where the heat capacity is small. Therefore, this sensor 13 detects the water temperature, but when the outside temperature is high such as in summer, the sensor 13 detects the temperature of the outside air and further detects the water temperature.
When the amount of hot water used is small, the sensor 13 misidentifies the temperature as being over 35°C even though there is low-temperature water at the bottom of the tank 1, and the heat pump does not operate and generates heat. As a result, the heat pump does not operate economically even though it is actually in a state where it can be operated. According to experiments, it was found that when the outside temperature was 31°C and the water temperature was 28°C, and 100% of the hot water in the hot water storage tank 1 had been used, the heat pump would not operate the next time the power was turned on. This phenomenon occurred from summer to mid-season, and had the disadvantage that it was not economical to operate for a long period of time depending on the household using it.

The present invention solves the above-mentioned conventional drawbacks, and aims to promote economical operation by accurately controlling the operation of other heat source equipment according to the hot water supply load.

In order to achieve the above object, the hot water device of the present invention has the following features:
A hot water storage tank, a circulating water outlet provided below the hot water storage tank, a circulating water inlet provided at the top of the hot water storage tank and connected to the hot water supply inlet, and a circulating water inlet provided below the hot water storage tank,
A heating device that heats the water inside, a circulation section that connects the outflow port and the inflow port, a circulation pump provided in the circulation path, another heating device that heats the water in the circulation path, and the hot water storage tank. means for detecting the water temperature within the
means for detecting the water temperature in the circulation path on the primary side of the other heating device; and, when the water temperature in the hot water storage tank has not reached a predetermined temperature, a signal from the means for detecting the water temperature in the hot water storage tank for a certain period of time. Determine and energize either the heating device or the other heating device based on signals from a timer device that operates the circulation pump and a means for detecting the temperature of the circulating water after the timer device has finished operating. control means,
This allows for highly economical operation.

An embodiment of the present invention will be described below based on the drawings.

In FIG. 1, the hot water device forms a circulation path 6 that communicates with a water outlet 2 at the bottom of the hot water storage tank 1, a circulation pump 3, a heat exchanger 4, and an inlet 5 at the top of the hot water storage tank 1. . Furthermore, the hot water device is provided with a heat pump heat source device 11 that forms a heat pump cycle path 10 that connects the heat exchanger 4, expansion valve 7, evaporator 8, and compressor 9 with piping as another heating device. A fan 12 is provided near the evaporator 8 to introduce outside air. 13 is a return water temperature detection sensor that controls the operation of the heat pump heat source device 11, 14 is a boiling temperature detection sensor, and 15 is a timer that outputs an ON signal so that the circulation pump 3 operates only for a certain period of time based on the signal from the return water temperature detection sensor 13. A device 16 is a heating element and is provided in the hot water storage tank 1. Reference numeral 17 denotes a variable resistor for arbitrarily variably setting the boiling temperature. 18 is an outer case that houses the hot water storage tank 1 and the like.

The heat pump heat source device 11 absorbs heat from outside air, exchanges the heat with the heat exchanger 4, and converts water in the circulation path 6 into hot water. In this example, the efficiency is
COP3.5 or higher. So for example capacity 370
The water in the hot water storage tank 1 is transferred to the heat pump heat source device 1.
First, boil the water to the specified temperature of approximately 55℃ using only 1. The required time is less than 3 hours with an input of 1300W, making it extremely energy-saving compared to general electric hot-wire water heaters. After the heat pump heat source device 11 is stopped, heating is switched to heating by the heating element 16, and the heating is further heated to a high temperature set temperature of 85°C.

In this way, this hot water system is equipped with late-night power supply zone 8.
The heat pump heat source device 11 is operated preferentially during the specified time, first heating up to 55 degrees Celsius, and then energizing the heating element 16 as necessary to save expensive electricity and reduce running costs. be.

The operation of the above configuration will be explained below.

In Figure 2, the late-night power supply zone is reached and the voltage is 200V.
When the power is turned on and the water temperature detected by the boiling detection sensor 14 is below the set temperature of 55°C, an output signal from the boiling detection sensor 14 indicating that the water has not boiled to the predetermined temperature is input to the boiling detection unit 19. be done. Then, the timer device 15 is turned on, the relay 20 is turned on, and the normally closed contact 21 becomes a circuit, and the load contact 23 becomes a closed circuit. At this time, the heating element 16 is still in a stopped state. As the circulation pump 3 operates, water in the hot water storage tank 1 circulates in the circulation path 6, and a return water temperature detection sensor 13 detects the temperature of the circulating water. When the timer device 15 is turned off, the normally closed contact 21 of the relay 20 is closed, and the load contact 23 is closed. When the normally closed contact 21 is closed, the relay 24 is energized and its load contact 25 is also closed. At this time, if the water temperature detected by the return water temperature detection sensor 13 is 35°C or less, the heat pump heat source device 1
It is determined that it is necessary to operate the heat pump heat source device 11, and the heat pump heat source device 11 is started to operate. That is, the boiling temperature detection sensor 14 outputs a signal to the relay 24, and the return water temperature detection sensor 13 outputs a signal to the relay 26. Therefore, the relay 2 is connected in series to the relay 27, the compressor 9, and the fan motor 10.
The load contact 28 of No. 6 becomes a closed circuit, and the load contact 28 of No. 6 becomes a closed circuit.
Contact 29, which is in a reverse contact relationship with 8, becomes an open circuit. Further, current flows through the relay 27, and the load contact 22 of the relay 27 connected in parallel to the 100V power supply is also closed. The circulation is continued by the circulation pump 3, while the heat pump heat source device 11 circulates the heat medium in the direction of arrow G in FIG. 1, and exchanges heat with the circulating water by the heat exchanger 4. The heated circulating water flows into the hot water storage tank 1 through the inlet 5, and the heat pump heat source device 11 operates until the temperature of the entire amount of hot water in the tank reaches the set temperature of 55°C. When the return water temperature detection sensor 13 installed in the circulation path 6 detects that the temperature has reached 35°C or higher, the load contact 28 of the relay 26 and the load contact 22 of the relay 27 are opened, the heat pump heat source device 11 is stopped, and the circulation pump 3 will also stop. On the other hand, only the contact 29 is closed due to the reverse contact action, the heating element 16 is energized, and the hot water in the hot water storage tank 1 is further heated to the hot water temperature set by the user. For example, if the user sets the water temperature to 85°C, the contact 25 of the relay 24 is opened by the output signal of the boiling temperature detection sensor 14 when the water is boiled to this temperature, and the heating element 16 is no longer energized. It will stop and boiling will be completed.

The above operation has been explained using an example where the water temperature detected by the boiling detection sensor 14 is 55°C or less when the 200V power is turned on, and the returned water temperature after the timer device 15 ends is 35°C or less. Even if the boiling detection temperature is 55°C or higher, the same operation will be performed if the return water temperature is 35°C or lower. However, if the detected boiling temperature is 55° C. or higher and the return water temperature is 35° C. or higher after the timer device 15 has finished operating, the heating element 16 is suddenly energized and the heat pump heat source device 11 becomes inoperable.

As described above, according to the present invention, the return water temperature detection sensor 13 effectively detects the temperature of the passing water after the operation of the circulation pump 3 is completed, so that it is possible to detect changes in the amount of hot water used by the user, Since water temperature is accurately detected without causing misjudgments due to temperature changes, heat pump operation can be performed in a timely and accurate manner. As a result, it is possible to provide the most economical energy-saving operating conditions throughout the year.

Furthermore, since the temperature inside the hot water storage tank is constantly detected, the circulation pump operates only when the temperature inside the hot water storage tank drops, making it economical.

Furthermore, since hot water is stored from above the hot water tank,
There is no residual water in the tank, and hot water can be used immediately even after hot water storage operation, so there is no waiting time.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the present invention. FIG. 2 is a block diagram of the water dispenser, and FIG. 2 is a control circuit diagram of the water dispenser. 1...Hot water storage tank, 3...Circulation pump, 4...
Heat exchanger, 6... Circulation path, 11... Heat pump heat source machine (other heating device), 13... Return water temperature detection sensor, 14... Boiling temperature detection sensor, 15...
...Timer device, 16...Heating element (heating device).

Claims (1)

[Claims] 1. A hot water storage tank, a circulating water outlet provided below the hot water storage tank, a circulating water inlet provided at the top of the hot water storage tank and connected to the hot water supply port, a heating device provided below the hot water storage tank to heat the water inside, and A circulation path connecting an outflow port and an inflow port, a circulation pump provided in the circulation path, another heating device for heating water in the circulation path, a means for detecting the water temperature in the hot water storage tank, and the above-mentioned others. means for detecting the water temperature in the circulation path on the primary side of the heating device; and when the water temperature in the hot water storage tank has not reached a predetermined temperature, the water temperature in the hot water storage tank is detected by a signal from the means for detecting the water temperature in the hot water storage tank for a certain period of time. A timer device that operates the pump; and a control device that determines and energizes either the heating device or the other heating device based on a signal from a device that detects the temperature of the circulating water after the timer device has finished operating. A hot water device equipped with.