Abstract: A refrigerant system is provided with tandem compressors. A tandem compressor arrangement includes at least two compressors operating in parallel and having at least one common manifold. A control may operate the compressors either simultaneously, or in some predetermined sequence to provide control over refrigerant system capacity. At least one of the tandem compressors is provided with a pulse width modulation control on a suction line. In this manner, the amount of refrigerant, compressed by the compressor, can be precisely controlled to exactly meet thermal load demands in the conditioned space.