Compressor Issues

[JeffM]

So yesterday one of my compressors burns a belt off. Long story short, pump tech comes by and says it is siezed up b/c it wasn't unloading properly and we need a new pump head. I ended up draining the tank last night and the pump can be turned by hand until the pressure gets up to about 100psi.

It seems that the pump head is being pressurized, making it impossible to run the pump. Would it make sence that a check valve has failed and is stalling the pump?

Any other ideas?

 

[MEP001]

Is the tank unpressurized? If the tank has 125 PSI and you can't turn the pump by hand when it gets to 100 PSI, you haven't really determined anything wrong at all. Is that pressure gauge just on the pump or are you building 100 PSI in the tank?

If the pressure switch is off and the unloader valve should be open and it's still building too much pressure in the head to turn by hand, then the unloader is bad, not the pump head.

If the tank has no pressure and the head still builds too much pressure to turn by hand, the check valve in the tank is stuck closed.

"Pump tech" is either lying to you to sell you a new pump or he's an idiot. If you can turn it by hand and make it build pressure, it's obviously not seized.

 

[JeffM]

When the tank is umpressurized the pump can be turned by hand until about 100psi. I ended up isolating the tank and unhooking the copper unloader line and turned it by hand until I built up some pressure.

Turns out the check valve is stuck open, and the way someone set up both compresors to turn on at the same time was by feeding the copper unloader line from the compressor with the failed check valve into the feed for the pressure switch on the good compressor. So neither of my compressors have been unloading for who know how long!

I reluctantly called this company to come service the pump as they are an IR dealer and the company I had used on the last 2 occasions has a new service manager who didn't want to work on an IR pump Needless to say I'm not impressed.

 

[MEP001]

I've had the same issues with IR people. They're quick to throw parts at a problem instead of diagnosing it properly. I went to replace a compressor that an IR authorized service person said needed a new motor because it kept tripping the thermal overload - not only was it on the wrong voltage and just needed bigger overload strips ($15), it had 50 gallons of water in the tank and was short-cycling.