Unloader function Champion R15A

by Ron
(South Mississippi)

My Champion R15A compressor bleeds air out the intake muffler when pressure is in the tank and the compressor not running.

Is this normal?

Other smaller compressors give a loud hiss when the motor stops running. I believe this is the unloader.
My Champion does not do this.
It just slowly leaks air back thru the intake.

Bleeding air out of the tank to reach the ON pressure (75#) sees the compressor start normally.

Pressure switch is set to cut off at 100# and on at 75#
Should these be set higher>

Ron in Mississippi

Comments for Unloader function Champion R15A

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Jun 22, 2018
Champion R15A unloader
by: Ronno6

Now as I examine this compressor in more detail, it appears to have a constant speed head unloader valve in the low pressure intake manifold.
I do not believe this is of use, and not even sure if it is functioning.
There is a 1/4" or so copper tubing from the HP exhaust manifold to a tee atop the governor, which I had thought to be the unloader, and it then is connected to the top of the aforementioned head unloader valve.
Any idea as to what I have here and how it should function?

Jun 22, 2018
Champion 15A
by: Ronno6

It took some wrenching and a few bucks for parts and fittings, but the air is being made hard again.
However, the unloader still does not really dump air with a loud hiss; but rather, a slow discharge thru the unloader tube.
I don't know if the tubing is clogged or what, but it does unload, it just takes about 10 to 15 seconds to do so.
I don't think the compressor will ever cycle that quickly.
Thanks for your help!

Jun 18, 2018
R15A check valve
by: Ronno6

Upon further inspection and complete disassembly of the entire discharge line from head to tank, I find NO check valve! There were other strange things about this setup that leaves me wondering......
The pipe entering the tank is 1/2" npt, so I have ordered a like sized in-tank 1/2M x 1/2F threaded check valve.
Also, the lop pressure exhaust valve was in pieces and non functional prior to my replacing the valves.
I have to think that maybe the unloader valve had been disabled, so I have a new kit coming for that as well.
Possibly that is why the pressure switch was set at 100# max 75# min so that the compressor might be able to start against a 75# head ??
There has been no unloader dump hiss......

Jun 17, 2018
by: Ronno6

I will pursue the check valve you cite.
I just replaced the intake valve.

Jun 17, 2018
Unloader function Champion R15A
by: Bill

"Is this normal?" Nope.

Way I see it you have two problems with your R15A - at least.

Once is that your tank check valve is leaking and two, you may have an intake valve that's failing.

Pages on how to fix these can be found on this site.

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