Compressor problem

[Rick Fisher]

Its happened twice now .. The compressor is an 80 Gallon Champion with a 5hp Baldor motor.. (Its about 2 years old, I think) .. only been hobby used. I doubt it has 40 hours on it.. dunno ..

The motor has an FLA of about 23 amps. Its wired to a 40 amp breaker.

It starts up fine. Takes about 4 minutes to reach 150 PSI .. Nothing has changed.. Most of the time, it just runs fine. no big deal. I use it to supply a small wide belt sander various other things..

When kicking back on at say 110 PSI ... to refill the tank, it works fine about 90% of the time, the other times, it makes a terrible sound, makes a weird smell, and kicks the 40 amp breaker on the panel.

I think the smell is the belt slipping. The pump won't turn easily .. Its like the 110 Psi is too much for the motor to get the pump running again. The weird thing is that the compressor is managed by an Allen Bradley Mag starter. I'm surprised the 40 amp breaker trips and not the reset.

Here is a picture of the beast new..

http://i335.photobucket.com/albums/m455/jokerbird_photo/P1000575.jpg (http://s335.photobucket.com/user/jokerbird_photo/media/P1000575.jpg.html)

[Jerry Bruette]

Sounds like your unloader isn't working all the time. That means it's starting under pressure and the motor can't turn the pump.

Or you have a discharge valve that's sticking open and the cylinder of the pump is under a load.

[Jim Andrew]

Only thing I could suggest would be to put synthetic compressor oil in it.

[Carroll Courtney]

Jerry has very good suggestions,I was also thinking the check valve sticking.With that brand which is the best compressor made I would also maybe check with Champion,maybe they have a help desk or tech support.I also like Jim's suggestion but check with Champion on that also.

[Duane Meadows]

Unloader maybe. Check valve more likely.

[Bill White]

I bettin' on the PRV (pressure relief valve)/unloader. Get it fixed before you burn up something.
Bill

[Rick Fisher]

The oil level in the pump is normal. I don't believe the pump is failing.. I ran it up to pressure again today from zero, no problem. I just don't want to leave it unattended. I can run my sander for an hour off the air in the tank.. lol.. so its not really a huge deal. I just cant use air sanders ...

I'll contact the Champion dealer after boxing day .. until then I will treat it gently. Its been great until now. I think a replacement pump for that machine is over $1000 .. so I will get on it asap..

[Rick Fisher]

How would I check the un-loader valve ?

This compressor has a thing it does where it pumps up to 155 psi.. then when it shuts off, it blows 5 psi out a tiny tube.. Which sounds horrible.. Its supposed to remove any water from the tank .. So for about 10 seconds after it shuts off, it drown's out any other sounds I could be listening for ..

[Steve Rozmiarek]

Rick are you sure its supposed to vent that 5psi out? That sounds a lot like a pressure relief popping. I usually run lower psi, but have seen some factory reliefs set around that level.

[Bill Ryall]

Sounds like the unloader is sticking. If the unloader sticks, the motor/belt will be trying to start the cylinder under high pressure. The smell is the belt burning and the breaker trips due to the very high current being drawn by the motor trying to compensate for the load.
My 3hp, 26 gallon Frankenstein compressor exhibited the same symptoms as the unloader began to fail.

[Rick Fisher]

Bill .. is the unloader the same as the pressure switch ? Or is it the piece that looks like a space ship ..

I will start googling ..

[Jerry Bruette]

Rick try a google search for Champion r15 manual or breakdown. r15 is the model of the pump you have.
http://www.flamingoshopserv.com/portals/2/news/partsbreakdown/champion%20r15%20breakdown.pdf

Here's a link to the manual, page 15 talks about the unloader and check valve. Your problem could also be the 2nd stage discharge valve not closing all the time--could have a piece of dirt in it .

Hope this helps.

[Bill Ryall]

Rick- some pressure switches have a built in unloader. Some compressors have a separate unloader. My big Frankenstein compressor has a separate unloader, while my little oil filled 9 gallon general purpose compressor in the woodshop has one built into the pressure switch. Check your documentation.
The unloaders are like any other moving mechanical part. It needs to be used regularly to keep it from sticking.