A self-modulating scroll compressor includes a pair of valves. A first valve
moves
to a low capacity position when the pressure differential is below a predetermined
amount. A second valve moves to a low capacity position when the suction pressure
is above a predetermined amount. Low capacity operation will only occur when both
valves are open. The present invention thus provides a scroll compressor design
with the ability to self-modulate and control the conditions under which low capacity
operation occurs based upon two criteria.
