Bought a air compressor, have questions....

[Brandy]

Hi all, I bought a Brunner air compressor yesterday and hooked it up 220v today. It runs great and is real quiet, I had a conversation standing next to it while it was running and neither of us had to raise our voices. The thing is, I cant find any info on it. it has a Brunner plate on the tank side and that's it. No other tags, numbers, stampings or castings anywhere. The pressure gauge at the air out end goes to 300 psi and looks like it's from the 40's or 30's. Two stage compressor, all cast iron. 5 hp Dayton motor. It needs a pressure switch diaphragm though. What I want to know is how much this thing will hold for pressure? Can I replace that original pressure switch with a new one that has the same number of outlet/inlets? How many gallons is the tank? 60...80? How old is it?

Thanks, see the attached pic.

 

[miller]

Hiya, Ghostrider 67...

Fairly hard to find much on Brunner compressors. Stopped making them in the 50s(?), or something like that.

I, too, have an old Brunner. Mine's an upright. Heavy as hell. I've got my pressure switch set at 150 pounds...probably about max where you should have yours. You should be able to replace the pressure switch, just find one with the right range on it.

 

[mosquito13]

2nd the 150 lb max

 

[chooch]

try giving these people a call I've always had good luck with them no matter how old & obsolete http://www.kruman.com/Air-Compressor-Parts-Pittsburgh-PA.html

not trying to nit pick but I'd hate to see anything bad happen but it looks to me that you have a 12-2 or 12-3 wire feeding a 220 on your compressor??

 

[Brandy]

yes, 12-2 with ground on a 20 amp double pull breaker. What? Is that too small? Should I use 10-2 w/ ground? Also, I discovered that the pressure switch diaphragm has a hole in it and has gunk built up under it too. I used the wire cup brush to clean that off but need some natural rubber sheet to make a ne one. I just finally located a sheet of 1/16 th rubber ( 1.5mm) for 6.00 bucks at Grainger supply. Thanks for the link chooch!

 

[chooch]

you might want to talk to a electrician but I think 12-2 might be a little bit to light of a wire, I ran 10-2 on mine with a sub panel disconnect at the compressor since it has no on / off switch but I also had to run 20ft of wire my thought being the long run time the compressor might have if your using it a lot. I personally wouldn't even play around with the psi switch & buy a new one if you can since there pretty cheap it's not worth the chance of it not working..

 

[Brandy]

I agree, I just got off of the phone with Brian at Kruman and he suggested the same. He told me that Brunner only made the compressor and the tank. All other fittings etc are generic so I can get a new switch from Grainger and put it on. The compressor has two relief valves and the tank two as well. I watched a video of a electrician wiring up a 5 HP 60 gallon 2 stage compressor and he recommended 12/2 w/ ground. I will ask around though. Thanks for the input.

 

[bm02tj]

If it need 30 amp breaker you need 10-2 20 amp 12-2 unless the wire run is long then you need to upsize wire

 

[Brandy]

How long is "long"? I ran 40 feet.

If it need 30 amp breaker you need 10-2 20 amp 12-2 unless the wire run is long then you need to upsize wire

 

[bm02tj]

It is usually 100 feet to be long
what is the amperage listed on the motor
it is the key item

 

[Brandy]

it is 21.0 amps. I have it on a double pull 20 amp square d breaker. This breaker box is on a wall in the hall to my garage which is separate from the house but the box has no main that I can cut off because the power comes from the big box in my homes basement, I have to cut it off from there.

 

[bm02tj]

you need a 30 amp breaker and 10 gauge wire

 

[Brandy]

Got the 12x12 inch sheet of natural rubber today and cut a new diaphragm out of it. It works fine. Cuts out at 145psi and back in at 95psi. I'm going to play around with adjusting it. But all is well.

 

[miller]

Pressure sounds good to me. Is there a label or tag on the tank itself, telling max psi? Either way, your 145 psi will do any thing you want it to do.

Heck, your deal probably gets pressure faster than my old Brunner, that takes around 15-20 minutes! But, the old gal's been around the block.

 

[440roadrunner]

THERE IS NO WAY I would use that TANK without HYDRO testing which you can easily do YOURSELF

Pull the tank / compressor apart, and plug all fittings except one "at the top." It is best to prop up the tank to form "the least" cavity at your top test fitting.

Fill it completely with water. Get all air out clear to the top of your fitting. Position the tank carefully so this happens.

Then simply get "whatever" fittings you need and a pressure source that is NOT oxygen or flammable. I just use CO2. "Rig" the pressure source to the tank and pressure it up to at least 2X your operating pressure.

Some guys have even used grease guns, etc for a pressure source

Not a believer? Google it

 

[Brandy]

takes about 9 minutes.

Pressure sounds good to me. Is there a label or tag on the tank itself, telling max psi? Either way, your 145 psi will do any thing you want it to do.

Heck, your deal probably gets pressure faster than my old Brunner, that takes around 15-20 minutes! But, the old gal's been around the block.

- - - Updated - - -

hmmm... ok..i will. Thanks.

THERE IS NO WAY I would use that TANK without HYDRO testing which you can easily do YOURSELF

Pull the tank / compressor apart, and plug all fittings except one "at the top." It is best to prop up the tank to form "the least" cavity at your top test fitting.

Fill it completely with water. Get all air out clear to the top of your fitting. Position the tank carefully so this happens.

Then simply get "whatever" fittings you need and a pressure source that is NOT oxygen or flammable. I just use CO2. "Rig" the pressure source to the tank and pressure it up to at least 2X your operating pressure.

Some guys have even used grease guns, etc for a pressure source

Not a believer? Google it