JPS61165563A - Solar-heat utilizing water heater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a solar water heater comprising a refrigerant circulation closed circuit that collects solar heat and atmospheric heat, and a hot water supply water heating circuit that uses the collected heat to raise the temperature of water. It is related to.

Conventional configuration and its problems Generally, this type of solar water heater uses a heat collector.

It consists of a refrigerant circulation closed circuit that connects an accumulator, a compressor, a condenser, and a pressure reducing device, and a hot water heating circuit that connects a heat exchanger that exchanges heat with the condenser, a hot water storage tank, and a pump. A capillary tube can be considered as a pressure reducing device for a refrigerant circulation closed circuit having the above configuration, but if the capillary tube is operated throughout the year, the amount of refrigerant suitable for the refrigerant evaporation capacity in the collector will be transferred to the collector. It is impossible to supply to That is, if the capillary tube is selected to be suitable for the summer season when the refrigerant evaporation capacity is high, in the winter season when the refrigerant evaporation capacity is low, the refrigerant supply I to the collector increases, and the refrigerant liquid returns to the compressor. There is a problem in that the reliability of the equipment is reduced due to damage to the compressor components. On the other hand, if the capillary tube is selected to be suitable for winter when the refrigerant evaporation capacity of the collector is small, in summer when the refrigerant evaporation capacity is large, the discharge temperature of the compressor will rise due to an increase in the degree of superheating of the refrigerant on the suction side of the compressor. There were problems such as a decrease in system operating efficiency.

In addition, in this system, the refrigerant evaporation capacity of the collector changes due to instantaneous fluctuations in solar radiation and outside wind speed, so if the pressure reducing device is a capillary tube, the degree of refrigerant superheating on the suction side of the compressor can be changed to an instantaneous refrigerant evaporation capacity change. However, it is impossible to set an appropriate value for the refrigerant, resulting in the refrigerant returning to the compressor or excessive superheating of the refrigerant, resulting in problems such as a decrease in the reliability of component equipment and a decrease in system operating efficiency. Further, a temperature-type expansion valve can be considered as the pressure reducing device, and an external pressure-equalizing temperature-type expansion valve is generally used in consideration of the effective use of a heat collector that evaporates the refrigerant. When the pressure drop exceeds 0.4:q/crA, hunting of 0.2 to 0.3 Kid/(- will occur on the low pressure side of the cycle due to leakage of the external pressure equalization type temperature expansion valve. As a result, there was a problem in that the reliability and durability of the compressor decreased due to load fluctuations on the compressor motor.In addition, hunting caused by leakage of the external equalization tube of the external pressure equalization type temperature expansion valve caused components of the temperature type expansion valve to deteriorate. There was also a problem with the durability of the diaphragm.

Here, Fig. 1a shows the hunting state of the low pressure PL caused by the leakage of the external equalizing pipe of the external pressure equalizing temperature expansion valve when the pressure loss of the heat collector is large, as well as the high pressure PH. Figure 2 shows the state of low pressure PL and high pressure PH when the pressure loss of the heat collector is reduced. According to this, low-pressure hunting can be prevented by increasing the pipe diameter of the heat collector and reducing the pressure loss when the refrigerant passes through the heat collector in order to reduce the leakage of the external pipe of the external pressure equalization type temperature expansion valve. Generally, when a heat collector is installed on the roof like in this system, a long connection pipe is required to connect the heat collector and the compressor, and if the pipe diameter of the heat collector is increased, the compressor There was a problem in that the amount of refrigerant required for the system was greater than the allowable amount of refrigerant, reducing the reliability of the system.

OBJECTS OF THE INVENTION The present invention solves such conventional problems, and the amount of refrigerant that is suitable for the change in refrigerant evaporation capacity of the collector, in which the refrigerant evaporates due to changes in outside air temperature, solar radiation, and outside air wind speed, is adjusted to the amount of refrigerant in the collector. It also prevents low-pressure hunting in the refrigerant circulation closed circuit caused by leakage of the external equalization tube of the external pressure equalization type temperature expansion valve when the pressure loss when the refrigerant passes through the heat collector is large. The aim is to improve the reliability and durability of decompression equipment.

Composition of the invention To achieve this objective, the present invention provides a heat collector.

In a refrigerant circulation closed circuit in which an accumulator, a compressor, a condenser, and a pressure reducing device are connected, the pressure reducing device is an internal pressure equalization type temperature expansion valve. With this configuration, when the pressure drop of the heat collector is large,

Hunting that occurs at low pressure in the refrigerant circulation closed circuit due to leakage of the external tube can be prevented, the durability and reliability of the compressor and thermostatic expansion valve are improved, and stable heat collection operation is possible.

Description of examples An embodiment of the present invention will be described below based on FIG.

In the figure, 1 is a heat collector that collects solar heat and atmospheric heat and evaporates the refrigerant, 2 is an accumulator, 3 is a compressor, 4 is a condenser that condenses the refrigerant, and 6 is an internal pressure equalization temperature expansion valve. Heater 1. Accumulator 2. Compressor 3. The condenser 4 and the internal pressure equalization type temperature expansion valve 6 constitute a refrigerant circulation closed circuit. 06 is an adsorption-filled type temperature sensitive cylinder of the internal pressure equalization type temperature expansion valve 6, and is arranged at the outlet of the heat collector 1. It is set up. Further, 7 is a heat exchanger that absorbs heat released from the condenser 4, 8 is a hot water storage tank, and 9 is a pump.
The hot water storage tank 8 and the pump 9 constitute a hot water heating circuit, which together with the refrigerant circulation sealed circuit constitutes a solar water heater.

10.11 is a connecting pipe.

Next, the operation of the solar water heater having the above configuration will be explained. The high-temperature, high-pressure refrigerant gas compressed by the compressor 3 flows into the condenser 4, and uses the heat of condensation to heat and raise the temperature of the low-temperature water sent by the pump 9 of the hot water heating circuit, and stores it in the hot water storage tank 8.

On the other hand, the refrigerant that has been liquefied by being deprived of condensation heat flows into the internal pressure-equalizing temperature expansion valve 6, is depressurized, flows into the collector 1, absorbs solar heat and atmospheric heat, becomes evaporated, and passes through the accumulator 2 to the compressor. Return to 3. The pressure drop in the heat collector 1 of this system is 0.4 to 0-7 Kq when operated throughout the year.
/cnl. In the case of using the internal pressure equalizing temperature expansion valve 6 in the pressure reducing device as in this embodiment, hunting does not occur in the low pressure, and the low pressure changes in response to changes in the refrigerant evaporation capacity in the heat collector due to changes in solar radiation, outside air wind speed, etc. are doing. This means that
This is because the external pressure equalization type temperature expansion valve 6 eliminates the leakage of the external equalization pipe caused by the increased pressure loss of the heat collector 1 by changing to the internal pressure equalization type temperature expansion valve 5.

In addition, the set values of the internal pressure equalization type temperature expansion valve 6 of this embodiment are 1.85 to 97- under the condition of temperature sensing cylinder 0''C, and overload,
Since the static superheat level of 2 to 3 degrees was achieved through low load, it can be said that there are no problems with system operation.

Effect of the invention The present invention relates to a heat collector, an accumulator, and a compressor.

In a refrigerant circulation closed circuit that connects a condenser and a pressure reducing device, by using an internal pressure equalizing temperature expansion valve as the pressure reducing device, the external pressure equalizing temperature expansion valve can prevent leakage from the external equalizing pipe caused by increased pressure drop in the collector. It can prevent low pressure hunting, prevent periodic load fluctuations to the compressor motor caused by low pressure hunting, and prevent changes in outside temperature.
This makes it possible to control the refrigerant flow rate to adapt to the refrigerant evaporation capacity in the heat collector, which changes due to changes in solar radiation or outside wind speed, and has the effect of improving system reliability and durability.

[Brief explanation of drawings]

Figure 1 shows that when the pressure loss is large in a conventional heat collector,
Time of refrigerant circulation closed circuit to explain low pressure hunting caused by external pressure equalization leakage of external pressure equalization type temperature expansion valve -
Pressure diagram, FIG. 2 is a configuration diagram of a solar water heater according to an embodiment of the present invention.0 1... Heat collector, 2... Accumulator, 3... ... Compressor, 4... Condenser, 6...
...Internal pressure equalization type temperature expansion valve. Name of agent: Patent attorney Toshio Nakao and 1 other person
- Yuki Takumi - It's a meeting” d -1b
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Claims (1)

[Claims] It consists of a refrigerant circulation closed circuit that connects a heat collector, an accumulator, a compressor, a condenser, and a pressure reducing device, and a hot water heating circuit that connects a heat exchanger that exchanges heat with the condenser, a hot water storage tank, and a pump; A solar water heater that uses an internal pressure-equalizing temperature expansion valve as a pressure reducing device.