Expansion Valve: Description and Operation

A/C VARIABLE ORIFICE TUBE
A Variable Orifice Valve (VOV) is installed in the liquid line between the outlet of the condenser and the inlet of the evaporator. The inlet end of the Variable Orifice Valve has a nylon mesh filter screen, which filters the refrigerant and helps to reduce the potential for blockage of the metering orifices by refrigerant system contaminants. The outlet end of the tube has a nylon mesh diffuser screen. The O-rings on the plastic body of the VOV seal the tube to the inside of the liquid line and prevent refrigerant from bypassing the metering orifices.

The VOV is only serviced as an integral part of the liquid line. The VOV cannot be adjusted or repaired and, if faulty or plugged, the liquid line unit must be replaced.