A19712 Check Valve 1/2 NPT x 3/8 Compression with 1/4 Compression Relief for Unloader

A19712 Check Valve is a  1/2" NPT pipe thread into the air compressor tank with a 3/8 male compression fitting for the discharge line from the air compressor pump.
This check also has the 1/4 compression fitting installed for the small 1/4 inch unloader line.

A faulty check valve can cause the pump to labor on restart and with a fully pressurized tank can cause the motor to overload and blow circuit breaker or damage other components.
 

Service Note:
Always make sure to to off power and drain the tank before performing any air compressor repairs the repairs.