Vehicular refrigerating cycle with a bypass line

A vehicular refrigerating cycle comprising a compressor, a condenser for condensing refrigerant compressed by said compressor, an expansion valve, an evaporator for evaporating refrigerant adiabatically expanded by said expansion valve, a by-pass line detouring said condenser, a line switching means for supplying compressed refrigerant either to said condenser or into said by-pass line, and a capacity control means for variably controlling the capacity of said compressor corresponding to variations of its own suction pressure, said compressor being a variable capacity compressor the capacity of which automatically is decreasing with a reduction of its suction pressure, wherein said capacity control means is provided with setting means allowing the capacity of said compressor to begin to decrease from a maximum capacity first under a suction pressure of 2 atmospheres (absolute atmospheric pressure) or less in a state in which the refrigerant flows through the condenser without passing through said by-pass line.