What does a rotary screw compressor inlet valve do?

The air compressor inlet valve regulates the capacity of your rotary screw compressor. The air compressor unloader valve regulates the amount of air that is sucked in by your air compressor. By opening and closing the air intake, the capacity of a rotary screw compressor is regulated.

What is a compressor unloader valve?

A compressor unloader valve is a small component, typically measuring around 4-5 inches in length and width, which performs the critical function of releasing trapped air inside the tank. By doing so, it enables the motor to restart. An unloader valve malfunction is one of the more common air compressor issues.

How does an unloader valve work on a reciprocating compressor?

An unloader valve works on a reciprocating compressor, by releasing compressed air that’s trapped over the piston, between the pump’s cylinder and the tank check valve when the compressor reaches the cut-out pressure and stops.

Where is the unloader valve located on an air compressor?

The unloader valve will most likely be located inside the pressure switch or attached to it on most air compressors. During the operation of the air compressor, the switch turns the compressor off which activates the unloader valve.

Where is a pilot unloader valve located?

Above is an unloader valve diagram where the valve is attached to the pressure switch. However, the unloader valve can also be located next to the compressor on larger-scale air compressors. Here, a pilot unloader valve is used to control the emerging air pressure into the unloader valve. How Does an Unloader Valve Work?

How does a compressor 'unload' work?

When the desired pressure is reached, the compressor will go in 'unload' mode: the unloader valve will almost completely close the air intake of the compressor. This way, no more are can be sucked in and compressed, so the compressor is basically just turning around, doing nothing.