All PE reversing valves, 2-way, 3-way, or 4-way, work on the same basic principles. They function to cause a positive charge in the direction of refrigerant flow within the system. The pin guided interchange spool opens or shuts discharge and suction ports through the direction of pressure differentials between the high and low side of the system. The reversing valve consists of the main body, a pilot solenoid valve body, and a special PE coil. Many valves in field service have been cycled over 1,000,000 times without malfunction.
Pilot Solenoid Valves – Built into every PE reversing valve is a pilot solenoid, which alternately opens and closes the gas paths from the end of the chambers. This permits high-pressure refrigerant in one of the end chambers to reverse the position of the interchange spool. As the solenoid is energized, a gas path is closed to suction; when it is de-energized, the original open and closed gas paths are obtained.