If your air compressor starts up fine on the first start of the day, but stalls and makes a loud humming sound on subsequent tries, you’ve got a bum “Unloader” valve. The air compressor unloader valve is what makes the “Psssssst” sound when the motor shuts off after reaching operating pressure. The air compressor unloader valve is usually built into the pressure switch assembly.
10-21-2016, 01:58 PM #3. 10-21-2016, 03:16 PM #4 Chances are it’s crap in the valve / making it stick, ………. look up unloader valves on the web, they’re usually quite simple,. L. 10-22-2016, 01:16 PM #15. Im willing to bet its missing parts, there has to be a check valve and a way to unload the pump side of that once it gets to pressure, theres no magic, just a check valve and the pressure switch reliveing the line to the pump when it get to pressure, IMHO your pump looks like its been replumbed by some one at some point, no way are thoes 2 braided lines like that from the factory! A back flow valve into the tank, and then a small line going to your pressure switch/unloader valve.
Gas air compressor unloader valves are one of the numerous small, common and essential parts of an air compressor and the whole pressure maintenance process. The air compressor unloader check valve keeps the entire tank from draining and has a pipe running to the unloader valve. The air evacuating from the unloader valve does not stop the unloader valve from continuing leaking air after the compressor is stopped.
MORE INFORMATION ABOUT CHECK VALVES. If you have air leaking from any of the air pump lines or the pressure switch after the motor has shut off, you probably have a leaking TANK CHECK VALVE. Don’t confuse this with a discharge line, i.e. air hose or regulator, manifold, or other down stream air leak. The air compressor tank check valve is a one way valve designed to permit air flow into the air tank, but not out of the tank. There might be an open valve or air leak down stream of the air tank, in the air circuit that might be open dumping all the air pressure.
The pressure switch usually have an external unloader valve, and most times, it might have an internal unloader valve which incorporates an on/off switch on top, though not all valve have the switch. Regardless of how the line from the pump head or compressor is connected to the unloader valve in the pressure switch; an internal, underneath connection-like, the unloader valves perform the same function. From the ends of the hoses that fit directly into the unloader valve, cut two centimeters so that you will have fresh, unstretched hose material to attach to the valve.
how to fix air compressor unloader valve Related Question:
How do you know if your air compressor unloader valve is bad?
You can have two problems. Air leaking from an “unloader” valve on the pressure switch continuously (after the motor shuts off) is an indication of a leaking tank check valve, not a bad pressure switch. Air leaking from the unloader while the motor is running is an indication of a bad unloader valve.
How do I know if my unloader valve is bad?
Water leaks and inconsistent behavior are also signs of a potential failure in the near future. González: The typical signal when there is an unloader malfunction is a reduction of flow through the nozzle, which results in pressure loss. Dean: Typical symptom of an unloader failure is a sudden smooth pressure loss.
What happens if unloader valve is bad?
A failed unloader valve can cause high pressure at the nozzle. The unloader valve recirculates water to the pump inlet when the pump is running but the spray wand isn’t in use.
Does an air compressor need an unloader valve?
Yes, an air compressor needs an unloader valve. Extracting the air by the unloader valve is essential for the compressor motor to start again without any effort.
How does compressor unloader valve work?
How Does an Unloader Valve Work? When the air pressure inside the compressor’s tank reaches the pressure switch’s cut out pressure (the point when air is no longer delivered), the switch automatically trips off and interrupts the power supply to the motor.
Are all air compressor check valves the same?
There are so many reasons why air compressor check valves are used on air compressors. And, there are sometimes up to 5 check valves on a single compressor. It all depends on the compressor type, size and make/model of course. As said before, check valves allow the air to flow through in only one direction.
Why does my pressure washer dies when trigger released?
If a pressure washer stalls when the trigger is released, this usually indicates a fault in the unloader valve. It is a simple process to remove and replace the unloader.
Why does my pressure washer keep surging?
Surging occurs when the pressure is fine and then weakens. It is caused when the flow rate for the pump cannot be supported by the water supply. Problems can mount from there so it is important that it is dealt with as soon as possible.
