Refrigerant recovery and recharging system with automatic oil drain

摘要

A conduit is coupled to an oil accumulator with an orifice coupled in series with the conduit for limiting the flow of oil therethrough. A pressure sensor is coupled to the conduit for measuring the pressure in the conduit. An oil drain control solenoid valve is coupled to an electrical circuit also coupled to the pressure sensor for selectively opening the oil drain for the draining of oil into a collection tank without losing refrigerant.