Pressure dropping

by Jacques
(Bloomington, CA)

Why would a 2 hp compressor with a 20 gal tank pressure drops when using a 1/2 hp air tool.? Pressure drops to 40 PSI and won't recover as long as I am using the tool. Suspected compressor head and bought your manual but it does not cover how to rebuild it. It is a Speedair Model 3Z421G. The head as the following number on it 2Z499C. What's your recommendation?

___________________
Bill says...

Sorry Jacques, but I think your compressor is far too small to supply air to an air tool.

Read the specs on your air tool. What is the CFM requirement at what pressure?

Your 2 HP compressor can deliver, at the very most, about 7-8 CFM of compressed air at 90 PSI.

I suspect you will find that your air tool draws much more than that, and your compressor cannot keep up.

Read the pages on compressor Sizing on this site.

Cheers,

Bill