How to size an Air Compressor

[Roz]

Is there any rule of thumb for sizing a car wash air compressor for a simple self service car wash?

 

[soonermajic]

BIGGER is better

I know, TWSS!

 

[Greg Pack]

You don't need much. 3-5HP 230V single phase will work. Make sure it is 100% duty cycle.

 

[MEP001]

Make sure it is 100% duty cycle.

This is the most important part IMO.

 

[Bill Capron]

A dry lube compressor won’t last. Be sure it has a crankcase that you have to check the oil level in.

 

[Randy]

It all depends on how much air you need or what you’re going to be running. If it’s just a small 4 or 5 bay self-serve you can get by with a 20 gallon 100% duty cycle air compressor. If you have an automatic then you’re going to need something like a 60 gallon or an 80 gallon if you’re going to be using a lot of compressed air. The slower an air compressor runs the longer they will last. A lot of manufactures use the same pump but increase the pump speed so the air compressor will put out more CFM’s. Don’t EVER! think about buying an oil less air compressor, they are total junk, won’t last long in a car wash. In 1994 the night before we were to go on vacation the air compressor at the car wash died. We scrambled around and found a 20 gallon Sanborn at Builder’s Square, got there right before they closed. We installed the Sanborn thinking it wouldn’t last long. It’s still in service today, replaced the pressure switch once and rebuilt the motor once, I’m waiting for it to die, but it just keeps on chugging along, it runs real slow.

 

[Roz]

Thx for the info most helpful. Probably using a 6HP for a 5 bay SS.

 

[MEP001]

Thx for the info most helpful. Probably using a 6HP for a 5 bay SS.

I'd go with a pair of small vertical tank compressors, or one really good one and a small backup. My wash is six bay SS with one 7.5HP 80 gallon vertical tank two-stage compressor which hasn't been much trouble aside from the cheap Chinese motors. I keep hoping something major will go wrong with the pump so I can replace it with one of these:

Husky 80 Gal. 3-Cylinder Single Stage Electric Air Compressor C801H - The Home Depot

Husky 80 Gal. single stage air compressor provides high air flow with has 14 SCFM at 90 PSI and 155 PSI max working pressure giving the user optimum tool performance. The compressor features an oil-lubricated

www.homedepot.com

or two of these:

Campbell Hausfeld 10.2 CFM 3.7 HP 230-Volt 1 PH (VT6195) 60 Gal. Electric Vertical Single-Stage Stationary Air Compressor VT6195 - The Home Depot

The Campbell Hausfeld 60-Gal., 3.7 HP, vertical air compressor (VT6195) is ideal for a small shop, automotive enthusiast or serious DIY user. This compressor has high air flow of 10.2 CFM @ 90 PSI and

www.homedepot.com

 

[Twodose]

I would also install a magnetic motor starter.

 

[soonermajic]

Older is better. Get 30 yr old or more