Can anybody tell me what the little Red lever does or doesn't do on my Compressor .

Should it be in the up position as shown or down .

Unloader bypass maybe.....??

For auto mode or pressure switch perhaps?

It's a shut off switch.....  start it and then flip the lever. The compressor should stop.

 

Found this after........

Pressure Switch Function:

The pressure switch monitors the air pressure within the compressor's tank. It's designed to maintain a consistent pressure range by automatically starting the compressor when the pressure drops below a certain point and stopping it when the pressure reaches a preset maximum. 

Manual On/Off:

The red lever usually has an "ON/OFF" or "AUTO" setting. In the "ON" position, it allows the compressor to run automatically based on the pressure switch. In the "OFF" position, it stops the compressor from running, even if the pressure drops. 

Manual Cut-Off:

The lever also provides a manual way to shut off the compressor, which is useful for maintenance, or when the compressor is not in use. 

Auto-Off Disconnect:

Some pressure switches with a red lever also include an auto-off feature that disconnects the compressor from the power source when the lever is in the "OFF" position, providing an extra layer of safety.

 

 

On 7/20/2025 at 11:04 AM, dingdongrb said:

It's a shut off switch.....  start it and then flip the lever. The compressor should stop.

 

Exactly. Pressure switch turns off compressor when setpoint pressure is reached.

1 hour ago, RocketDog said:

Exactly. Pressure switch turns off compressor when setpoint pressure is reached.

So do I need to keep it in the upright position for normal running , then when it recharges the air tank it cuts out when it reaches the set pressure ?

 

7 hours ago, NE1 said:

So do I need to keep it in the upright position for normal running , then when it recharges the air tank it cuts out when it reaches the set pressure ?

 

If the air compressor motor starts up and fills the tank then stops, the switch is in the auto mode position and the compressor will start and stop by itself when you use the air for what ever reason.   

 

If your compressor tank leaks air, like mine does, for what ever reason and the air pressure drops below a certain level (mine is 80 PSI) then the motor starts up automatically and continues until the pressure reaches a certain level (mine is 140 PSI), then stops.   Then repeats continuously if it leaks.  This also happens when you use the air for tools, filling tires, etc. 

 

If you don't want your compressor to continuously fill and leak, fill and leak, fill and leak, when not in use, then move the switch into the opposite position from the auto mode.   All the air will leak from the tank and you will need to move the switch back to the auto mode before the compressor will start up and fill the tank again. 

 

PSI = pounds per square inch (of pressure)

1 Bar = 14.5 PSI