Patent ID: 8375741

Claim:
A refrigerant system comprising: a compressor assembly including at least two stages of compression connected in series, with a lower compression stage compressing refrigerant from a suction pressure to an intermediate pressure and passing this refrigerant to a higher compression stage compressing refrigerant from an intermediate pressure to a discharge pressure; an intercooler positioned intermediate of said lower and higher compression stages; a liquid/vapor injection function with a vapor injection connection positioned intermediate of said lower and higher compression stages; a heat rejecting heat exchanger positioned downstream of said higher compression stage, an evaporator positioned upstream of said lower compression stage and an expansion device positioned intermediate of said heat rejecting heat exchanger and said evaporator; at least one secondary fluid moving device for moving secondary fluid in at least one secondary fluid path over said heat rejecting heat exchanger and said intercooler; and said intercooler and said liquid/vapor injection function are selectively activated to control refrigerant discharge temperature depending on environmental and operational conditions as well as thermal load demands in a conditioned space.