Heat pump system of heat pump water heater

Abstract

The heat pump system is composed of compressor, condenser, throttling element, and evaporator connected in sequence through pipes. Coil pipe is wound on compressor, and two ends of coil pipe are connected to loop of evaporator. Advantages are: recovering quantity of heat released to environment by compressor before the invention; recovered quantity of heat is provided to evaporator to raise vapor pressure and to improve superheat degree of return-air of compressor in condition of low temperature. Test shows that in -5 deg.C of ambient temperature, thermal efficiency is raised 30%, and heating capacity is raised 35%. Since coil pipe is connected to loop of evaporator, thus, temperature of evaporator is higher than ambient temperature. The ambient temperature can be lowered than-5 deg.C when evaporator runs without frost. Or frost occurs defrosting cycle can be prolonged so as to raise efficiency of producing heat.

Description

technical field [0001] The invention relates to a heat pump system of a heat pump water heater, which is an improvement to the heat pump system of the existing heat pump water heater. Background technique [0002] The heat pump system of the existing heat pump water heater or the loop of the heating system such as figure 2 As shown, the heat pump system is mainly composed of a compressor 1', a condenser 2' (that is, a metal condensing coil), a throttling element 3', and an evaporator 4' connected in sequence through conduits. Its working mechanism is: refrigeration The agent comes out of the compressor 1' to form a high-temperature and high-pressure gas, which is introduced into the condenser 2' placed in the water storage tank of the water heater through the conduit, and after the condenser 2' exchanges heat with the water in the water storage tank of the water heater, it becomes a low-temperature and high-pressure liquid. Then it is introduced into throttling element 3' t...

AI Technical Summary

Problems solved by technology

However, in practical application of this heat pump system, it is inevitable to encounter two problems: one is that as the ambient temperature decreases, the evaporation efficiency of the evaporator 4' decreases significantly, and the suction and exhaust pressure difference of the compressor 1' Increase, the density of the refrigerant sucked by the compressor 1' decreases, and the circulation flow of the refrigerant inside the heat pump system decreases, resulting in a decrease in the heat provided by the heat pump system to the water storage tank, especially in winter when the ambient temperature is lower than -5°C Sometimes, its thermal efficiency is very unsatisfactory, and sometimes even the thermal efficiency is lower than 1, causing the heating capacity to fail to meet the requirements, and the hot water is not hot, which greatly affects the promotion of heat pump water heaters in the market and affects the heat pump water heater. The competition between the water heater and other traditional water heaters; the second is that when the ambient temperature is lower than -5°C, frost is easy to form on the outer surface of the evaporator 4', and the existence of frost will affect the evaporation of the coolant in the evaporator 4' Therefore, it is necessary to defrost the evaporator 4' regularly, and the shorter the defrosting cycle, the lower the heating efficiency of the entire heat pump system

Images