Air Compressor Won’t Unload: Troubleshooting

Unloading lets the compressor keep running at low load when air demand drops, and a fault wastes energy and wears parts.

How Unloading Works

The inlet valve closes and the blow-down valve vents pressure so the machine runs at minimum load.

Why It Fails

A stuck inlet valve, failed solenoid or blocked pilot line prevents the unit from reaching the unload state.

Diagnosis and Repair

Check the solenoid, pilot lines and inlet valve movement, and confirm the controller is commanding unload.

Contact us for inlet valve and unloader parts for your machine.