Cascade-heating multimode-coupled heat pump water heater

Abstract

The invention relates to a cascade-heating multimode-coupled heat pump water heater which comprises an evaporator, a first compressor, a first stop valve, a second stop valve, a second compressor, a first expansion valve, a second condenser, a first condenser, a water pump, a third stop valve, a fourth stop valve, a fifth stop valve, a sixth stop valve, a seventh stop valve, an eighth stop valve,a ninth stop valve, a tenth stop valve, a flow regulating valve, a water tank, a first water mixing valve, a second water mixing valve, a third water mixing valve and an eleventh stop valve. Accordingto the cascade-heating multimode-coupled heat pump water heater, two-stage compression and two-stage throttling heat pump cycle is switched in multiple modes to independently heat multiple stratifiedzones with different temperatures in the water tank; by switching the different stop valves, the separate heating mode for the stratified zones with different setting temperatures is realized in different coupling modes, and the mode of taking water from the stratified zones with different temperatures is adopted. The heat production efficiency is high.

Description

technical field [0001] The invention belongs to the field of heat pumps and relates to a heat pump water heater. Background technique [0002] With the gradual recognition of the market and the support of national policies, air source heat pump water heaters have been widely promoted, and users pay special attention to water comfort and energy saving. However, several important reasons for the low efficiency of traditional direct heat pump water heaters are the large heat transfer temperature difference between the refrigerant and the cold water, as well as throttling losses and compressor losses. Therefore, heat pump water heaters also need It consumes a lot of electric energy, and the efficiency is not ideal enough, so improving its electric efficiency is an important improvement direction. Existing heat pump water heaters can only heat water to a very high temperature and store it in the water tank. When users use hot water at a lower temperature, they can only use it af...

AI Technical Summary

Problems solved by technology

However, several important reasons for the low efficiency of traditional direct-heating heat pump water heaters are the large heat transfer temperature difference between the refrigerant and cold water, as well as throttling losses and compressor losses. Therefore, heat pump water heaters also need Consumes a lot of power, and the efficiency is not ideal enough, so improving its electrical efficiency is an important improvement direction

Existing heat pump water heaters can only heat water to a very high temperature and store it in the water tank. When users use hot water at a lower temperature, they can only use it after mixing hot water with high temperature from the water tank and mixing it with cold water. This process wastes the available energy in the hot water ( ), resulting in a large entropy production, reducing energy utilization, and having a single hot water temperature that cannot quickly meet the user's needs for different water temperatures; and when the heat pump system detects that the water temperature has dropped, it will automatically start to process the water in the entire water tank Hydronic heating, which is a waste of energy and hot water that cannot be quickly replenished to the user's desired temperature

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