Gas Heat Pumps (GHP) have very high efficiency, are designed for the winter and summer air conditioning of residential, commercial and big buildings. Small size natural gas driven GHP are also gaining ground and becoming more efficient around the world, as they offer significant amount of energy efficiency and carry additional environmental benefits. As a part of its developmental activity NAD (New Applications Development) team has developed gas engine driven heat pump (GHP). 
 
At present, the team has developed GHP unit for 4TR capacity. Here, we use gas engine driven refrigerant compressor, instead of the electric motor driven. Total system is controlled by the specially developed microprocessor based programmable logic control system ( PLC). This PLC enables maximum safety during GHP operation.