Performance of a Ground Water Assistant Air Source Heat Pump in Refrigerating Condition

Air-source heat pump has air as heat source; the system is simple, low initial investment. But the performance of air-source heat pump fluctuates big with the outdoor air temperature changes, especially in the summer hottest and winter coldest day, the cooling thermal capacity and the efficiency will significantly decline. In order to improve the air-source heat pump efficiency and thermal capacity in the summer hottest and winter coldest day, this paper put forward a ground water assistant air source compound heat pump (GWA-ASCHP) and test the cooling performance in rated and peak load conditions. The results show that the performances of GWAASCHP were improved observably by the assistant ground water. When the water flow is 50% of the single ground water source heat pump system, the EER of the GWA-ASCHP is about 30% more than the air-source heat pump in rated condition and the EER can be raised nearly 65% in peak cooling condition.