AbstractThis paper presents an investigation on using an ammonia refrigerant with liquid/solid absorbents in an absorber heat recovery cycle where heat released during the absorption process is used to heat up the strong solution coming out of the absorber, thereby reducing the generator heat input and hence improving the coefficient of performance. A comparative thermodynamic study is made with NH3‐H2O and NH3‐LiNO3pairs as working fluids for both conventional absorption and absorber heat recovery systems. It is found that an improvement of about 10 per cent in COP for the absorber heat recovery cycle is achieved over the conventional absorption cycle and the NH3‐LiNO3system yields a higher COP than for NH3‐H2O over a wide range of generator temperatures and condenser/absorber temperatures. A detailed parametric study is also presented in thi