In the present era, the refrigeration and air conditioning have become essential requirements, and consume significant portion of energy available. The refrigeration requirements are severe in the hot and humid countries and, the refrigeration systems based upon solar energy are desirable. This study focuses on the thermodynamic modelling of ammonia water diffusion absorption refrigeration cycle with helium as pressure equalizing gas. The performance of the cycle is investigated parametrically by computer simulation based on thermodynamic modeling. It is found that the performance shows a loss of 37.36% at 110[Formula: see text]C while only 23.52% at 140[Formula: see text]C a generator temperature in the range of 120 to 150[Formula: see text]C is best suited for ammonia concentration range of 0.25–0.45 to get optimum performance.