This paper proposed an absorption heat pump cycle of the type-II using water/diglycol as the working pair. Based on the principles of thermodynamics

a mathematical model describing this heat pump was established. The theoretical model was tested experimentally

and the calculated results agreed with the experimental results. The effects of operating conditions

such as heat source and sink temperatures

reflux ratio and heat transfer effectiveness of the solution heat exchanger on the performance of the heat pump were studied and analysed.