Defrosting end control method, processor and air energy heat pump hot water system

Abstract

The invention provides a defrosting end control method, a processor and an air energy heat pump hot water system and belongs to the technical field of heat pump hot water systems. The problem that inthe prior art, when a defrosting mode is ended, unmelted frost still exists on an outdoor heat exchanger is solved. The defrosting end control method comprises the following steps of entering the defrosting mode; and detecting data, wherein the detected data include temperature and pressure data, and the temperature and pressure data include the high-pressure pressure P of gaseous refrigerants exhausted from the exhaust end of a compressor in a heat pump unit, the temperature T of hot water in a water storage tank, the temperature Tp of the inlet end of the outdoor air side heat exchanger andthe like. The defrosting end control method, the processor and the air energy heat pump hot water system have the advantages that the air energy hot water system can be ensured to be completely defrosted during defrosting, and the water heating capacity of the air energy hot water system with probably unmelted frost at the low environment temperature is ensured when defrosting is stopped.

Description

technical field [0001] The invention belongs to the technical field of heat pump hot water systems, and in particular relates to an air energy heat pump hot water system. When heating water, due to the low outdoor ambient temperature, after a period of operation, the outdoor finned heat exchanger is thickly frosted, and can Defrost method to ensure that the unit defrosts cleanly. Background technique [0002] At present, the defrosting control method of the air energy hot water system is generally to first detect the temperature at the inlet of the outdoor finned heat exchanger coil and the heating running time. When the set value of heat running time and the temperature at the inlet of the coil is lower than the set value of defrosting temperature set by the system, the heat pump unit starts to defrost, and when the temperature at the inlet of the coil is higher than the set value of defrosting exit or defrosting When the frost running time is greater than the maximum defr...

AI Technical Summary

Problems solved by technology

[0003] This defrosting control method has the following disadvantages: When the frost is thick near the inlet of the finned heat exchanger coil, the defrosting of this part will be unclean.

Under long-term operation, icing occurs near the inlet of the finned heat exchanger coil, resulting in a significant drop in the hot water heating capacity of the heat pump unit. The reasons for this shortcoming are as follows: When the air source heat pump hot water system is defrosting, The low-temperature and low-pressure refrigerant is forced to exchange heat with hot water, absorbing a large amount of heat from the hot water, and then compressed by the compressor to become a high-pressure gaseous refrigerant that enters the outdoor heat exchanger (note: generally a finned heat exchanger), A large amount of heat is released for defrosting, and the frost in the outdoor heat exchanger will quickly melt away. When most of the frost melts, the high pressure of the heat pump unit will rise rapidly due to the fact that the outdoor fan is stopped. At this time, the outdoor heat exchanger will The defrosting speed of the frost near the inlet of the heater coil is lower than the rising speed of the high pressure. Before the frost is completely melted, the high pressure of the heat pump unit has reached the high pressure protection value set by the system, causing the heat pump to When the unit finishes defrosting and enters the hot water heating operation, since the part of the frost near the inlet of the outdoor heat exchanger coil has not completely melted and there is condensed water left during defrosting during the defrosting stage, the heat pump will When heating hot water, there will be icing phenomenon here, and as the running time increases, the icing will become thicker and thicker, and the icing area will become larger, which will seriously affect the heating efficiency