140-175 PSI 4 Port Air Compressor Pressure Switch Control Valve Import Style

Lefoo LF19A-H4 4-Port Air Compressor Pressure Switch Control Valve – Operating Pressure 140-175 PSI

The Lefoo LF19A-H4 is a universal, air compressor pressure switch designed to replace many of the import-style switches commonly found on compressors sold at farm stores, Harbor Freight, and other big box retailers. This model is factory preset to operate between 140 PSI (cut-in) and 175 PSI (cut-out) and fits a wide range of applications with its 4-port 1/4" NPT manifold.

This switch includes an integrated unloader valve to release pressure from the compressor head at shut-off, enabling smooth, load-free startups. The unloader elbow port on the bottom of the switch accepts 1/4" OD plastic, copper, or aluminum tubing but can be left disconnected if your compressor doesn’t use one.

Equipped with a manual ON/OFF lever, adjustable pressure settings, and six wiring terminals (line-in and motor, each with a ground), this switch is built to handle up to 26 amps at both 110-120V and 220-240V.

Commonly Found On:

• Import-style compressors

• Harbor Freight models

• Units sold at farm supply and big box stores

Specifications:

• Preset Cut-In: 140 PSI

• Preset Cut-Out: 175 PSI

• Adjustable Range: Minimum ON: 70 PSI / Maximum OFF: 200 PSI

• Ports: Four 1/4" Female NPT Connection Ports (add pipe nipples if male threads are needed) ports can also be plugged if not needed. (1/4" NPT measures approximately 1/2" in diameter)

• Unloader Valve: 1/4" push-to-connect (bottom-mounted)

• Wiring:

  • 2 Line-In Terminals + Ground

  • 2 Motor Terminals + Ground

• Amperage Rating:

  • 26 Amps @ 110–120V

  • 26 Amps @ 220–240V

• Red Control Switch: Manual ON/OFF

Note: While pressure is adjustable, we recommend staying within 15–20 PSI of factory settings for best reliability and switch life.