Disclosed is an integrated compressor system configured to be integrated with existing vehicle air conditioning systems. The integrated compressor system generally includes a mounting assembly (106), a first compressor having electric drive means (108) and a valve (110). The mounting assembly can be mounted directly on a condenser of an existing air conditioning system. The first compressor and the valve are mounted directly on the mounting assembly. The valve has a first valve inlet (166), a second valve inlet (168) and a valve outlet (170). When assembly and integrated with an existing AC system, the first valve inlet (166)is fluidly coupled to a compressor outlet (172) of the first compressor, the second valve inlet (168) is fluidly coupled to a compressor outlet of a second compressor of the of existing AC system, and a valve outlet (170) is fluidly connected to a condenser inlet of the condenser.