Will not start after sitting for an hour

by Isaac
(Luray, Va. )

The compressor is a Brute 15 gallon 2.50 HP. When you run the compressor it will restart as soon as the pressure drops but if you let it sit for an hour it will not start until the tank is empty. It ran fine and I moved it to use to put on a roof and when I moved it back to my shop the problem started

_________________________
Bill says...

Just so I'm clear, when you are using the compressor, it reaches cut out pressure fine, air pressure in the tank drops, and the compressor cuts in perfectly, fills the tank, and if you are not using the air, cuts out at the high pressure setting?

Then, after an hour, with full pressure in the tank, the compressor won't start?

Or, and hour later, you use the air that's in the tank, and when the pressure level gets to the cut in setting, the compressor won't start, and will not start until the pressure in the tank reaches zero?

Different issues here, and I need to better understand the sequence to try and provide assistance.

Before you write back, dump the air in the tank, turn off the power, and remove and clean both the unloader valve and the check valve. See if this makes any difference.

Good luck.

Bill