Compressor help

[Mori55]

I have a Challenge air 2stage pump model b2. It is mounted on a 60 gallon tank with a 5 Hp motor with a magnetic starter . I put this together years ago and it runs fine.
But I think I've been using the wrong pressure switch. It's a Fumas 69m B7Y it comes on at 95 and off at 125 . Seems to run a lot
Any help would be appreciated. Should i have one that goes on at 140 and off at 175 ? If so what model would I need?

 

[kams1973]

You need to find the max working pressure for you air tank first. Then the recommended max psi for the pump. Don't assume it's 175psi because it is a 2-stage unit.

 

[Mori55]

I searched the web and can't find my model pump. Only thing it says is model B2

 

[kams1973]

A brief search of "challenge air" brought up Curtis Air Compressors. Under the CA line, on C, D, & E pumps were listed. Your B2 may be an older pump. A pic of your pump would be helpful.

 

[Mori55]

The pump was bought in the early eighties , it looks exactly like one of the 5hp vertical 2stage pumps . I mean exactly , looks like same casting.
I bought the pump , motor , and starter new . I already had the tank. The pressure switch may have been already on the tank from a different pump. This I put together when I was a young man and always in a hurry.

 

[darkzero]

You need to find the max working pressure for you air tank first. Then the recommended max psi for the pump. Don't assume it's 175psi because it is a 2-stage unit.

+1

Your tank should have a plate on it that states what the max rated pressure it was certified for.

 

[Gregishome]

I have a Challenge air 2stage pump model b2. It is mounted on a 60 gallon tank with a 5 Hp motor with a magnetic starter . I put this together years ago and it runs fine.
But I think I've been using the wrong pressure switch. It's a Fumas 69m B7Y it comes on at 95 and off at 125 . Seems to run a lot
Any help would be appreciated. Should i have one that goes on at 140 and off at 175 ? If so what model would I need?

First determine what air pressure it is that you want to maintain. Really no sense in holding 160-175 psi full time if you are only running 50 psi tools of which 100 psi would do ( unless your sandblasting) .

If it is cycling a lot, you could have a small leak somehwere. Also look at the range stamped on the PS cover, you may be able to adjust it down.

 

[Mori55]

No leaks , most of my air tools require 90psi , I also have a glass beading cabinet.
PS 95 - 125 I think it's to low , can't adjust it , pre set .

 

[darkzero]

PS 95 - 125 I think it's to low , can't adjust it , pre set .

As kams1973 said, you really need to find out what psi your pump & tank can handle.

95 cut in & 125 cut out is the correct range for a 125 max psi compressor. Although you have a 2 stage pump I agree that is seems low as 125 is usually common on a single stage compressor.

You mentioned that you "put the compressor together" so it sounds like going off the specs of a Curtis B-2 is irrelavant unless you meant to say rebuilt. 2 stage pump doesn't mean you can run higher psi if your tank is not rated for it.

Most pressure switches can be adjusted, the ones that don'e have two or three visible adjusting screws usually have only one screw that is covered with hot glue or silicone.

But remember, if you go beyond your pump's capabilities you will blow seals or the reed valves & if you go beyond the tanks capabilites, well you will have a bomb. And if you do increase your pressure, you'll also have to use the proper sized pressure relief valve.

 

[PT Doc]

And if you do increase your pressure, you'll also have to use the proper sized pressure relief valve.

Dont forget this or all will be for naught.

 

[stltikn]

What does "seems to run alot" mean? Have you been using the air often? Did it just recently start "running alot"? What specifically prompted your question?
Reread all of the above answers. Do NOT exceed the pressure rating of the tank. Check the pressure relief valve setting stamped on the valve. Recheck for leaks. A very, very small leak at 125psi will cause the pressure to drop to your cut in pressure of 95psi. Check all of your fittings as well as the safety valve for leaks. Check the tank as well.

 

[Torque1st]

You don't seem to NEED higher pressure so leave the pressure switch alone. A two stage pump is more efficient than a single stage pump. Enjoy the power savings, -not much but every bit helps. Make sure you have no leaks and put a ball valve on the output of the tank.

Don't worry, -be HAPPY!

 

[Mori55]

I have zero leaks ! I bought the pump new originally. When I say run a lot , it seems to come on very quickly . I have been using it off and on for 20 some years.
I wish someone had a Manuel on a B2. The pressure switch I have was not part of the package, it was originally on the tank with the old pump. It is not adjustable.

 

[claymont]

When you say "run a lot" do you mean it's cycling more or taking more time to build the pressure back up? If the latter, you could be starting to see wear in components...less efficiency...longer run times.

I have zero leaks ! I bought the pump new originally. When I say run a lot , it seems to come on very quickly . I have been using it off and on for 20 some years.
I wish someone had a Manuel on a B2. The pressure switch I have was not part of the package, it was originally on the tank with the old pump. It is not adjustable.

 

[bad_idea]

The pressure switch only turns the pump on and off. Your PS is set at a range good for what you are doing. If the PS is causing the pump to run too long then the pressure in the tank would be going too high, or the unloader valve maybe partially open while running. Do you have a pressure gauge on the tank? Watch the pressure while the compressor runs. The PS should have a small copper line run to it, this is run to the unloader valve. Make sure the unloader valve isn't leaking by.

If the compressor is running more frequently then that would be leaks. Go over every fitting with soapy water, bubbles mean a leak. You can have a bunch of tiny leaks that you can't hear, and they add up to more frequent compressor cycling.

If the compressor is running for longer periods of time then the compressor pump is worn. Pull the head off and see if there is a bunch of carbon build up on the reed valves. Are the cylinders scarred up? A rebuild is as simple as a lawn mower engine. Unfortunately it sounds like you may have trouble finding a rebuild kit though.

Finally, check the relief valve to make sure it isn't partially stuck open. Should be an arm or ring on the top of it that you pull up on to test it. When you pull up on the arm or ring it should blow air and when you let go it should shut up. Verify it is completely closed by squirting it with soapy water.

 

[Mori55]

Thanks , but how many times do I have to say zero leaks? The tank does not leak down after weeks of sitting. Maybe i have the pressure thing wrong In my head. And yes the tank is fine. I was wondering why they show 145-175 in the Curtis 2 stage compressor that look exactly like my 2 stage. I think it's the same pump. And 95-135 on the single stage? There must be a reason ?
It got me thinking maybe I have the wrong switch. And no the compressor has very little time on it.

 

[e-tek]

I say you check for leaks.......


But seriously, I think you're right and you have the wrong PS. I READ your posts and you said the PS was with the tank and you added the pump.....so it's likely that you need a either a PS that goes 90-150, or an adustable switch and set it about that. That's where mine is, but still, even though mines a 2-stage, 3 cyl, 18.5 cfm at 100psi with a 175 max, it'll run a lot with the Sandblaster or high speed cut-off wheel.