BelAire 318V Pressure Switch

The BelAire 318V Pressure Switch is a four-port, bleeder-equipped control switch built for older BelAire 318V compressors, offering an adjustable operating range of 135–175 psi. Designed for 240V service with a full-load amperage rating around 26 A, it provides four 1/4-inch NPT ports for inlet, outlet, and auxiliary connections, plus a bleeder valve that accepts a 1/4-inch OD tube for venting and fine-tuning cut-in and cut-out pressures. Some listings indicate 120/240V compatibility, so verify the wiring configuration in your installation to match your power supply. Typically used as the start/stop control in BelAire portable and shop air compressors, this switch helps regulate pressure delivery by cycling the compressor on and off within the 135–175 psi window.