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dual air compressor plumbing

Reds

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I have 2 air compressors running 2 IBA's and 2 SS bays. Can I connect them both into my air lines and leave them on and running at the same time? Or should there be a check valve on one of the tanks to stop the other compressor from filling it? Both are set for approx. the same pressure at the moment. But I want them both hooked up and on so that if one fails the other will carry the load. If one is pushing a little more pressure than the other will it flow back into the compressor head of the other one causing resistance? Is there a factory check valve already between the compressor head and the tank? Right now I have them segregated from each other.
 

I.B. Washincars

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There is a check valve between the compressor pump and the tank. If you just hook the tanks together somewhere it will work. I don't see any need for a check valve between the two. If I were to want to expend a lot of brain power, I would want to figure out a way to shut them down in the event that a main hose or pipe breaks and they can't keep up and just run until they self destruct. Maybe a timed run length or another pressure switch to kill the power to the motor starter if the pressure gets below 20 lbs. or so.
 

robtl

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I have 2 air compressors running 2 IBA's and 2 SS bays. Can I connect them both into my air lines and leave them on and running at the same time? Or should there be a check valve on one of the tanks to stop the other compressor from filling it? Both are set for approx. the same pressure at the moment. But I want them both hooked up and on so that if one fails the other will carry the load. If one is pushing a little more pressure than the other will it flow back into the compressor head of the other one causing resistance? Is there a factory check valve already between the compressor head and the tank? Right now I have them segregated from each other.
Set one compressor about 5 psi higher and make a mental note when the oil is changed on the compressor or the tank is blown down switch the other compressor to run first, sort of a manual lead-lag system
 

Earl Weiss

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I have dual compressors at 3 locations (Tunnel applications) and they are not all set up the same.

At two places a single pressure switch trips two motor starters. The compressors always run together. I like this because they wear evenly. The tanks are simply T'd together with a valve on each so they can be serviced independantly if need be.

At the other place there are 2 pressure switches with the second a few pounds below the first. So the second only kicks on if the pressure gets that low which happens during heavy usage.

Pick your poison.

As Far as burning up if they run continuosly, the thermal overloads kick in if they get too hot.

To prevent this in the summer I have had to increase exhaust fan capacity and ad supplemental fans to cool the compressors and motors.
 

MEP001

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I added a second compressor - the added one was smaller and lower pressure. At first I had a check valve separating it from the larger one, but I later removed it and lowered the setting on the pressure switch for the larger one. I'm sure it's less wear on the motor to not have to start up so often; I can see no downside to it at all.
 

pitzerwm

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Another thing that I did was when one of my 80 gal ones blew up, I used that tank with the new one, the cycle time is cut down. So if you get a good deal on a tank get it.
 

Rudy

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This thread reminds me of what happened several years ago. My main (and only) compressor died completely. Of course, this was on a sunny Saturday winter day with 7 days of sunshine forecast. The only option on a Saturday afternoon....go to Home Depot and get a $450 cheapo to get over the hump.

We got it plumbed in and operational within an hour. On the side, however, it said, "Duty Cycle, 5 minutes on, 10 minutes off". Hmmmmmm

That cheapo ran for 6 days, 15 hours a day, almost straight with NO duty cycle. When I was finally able to get my permanent compressor (Eaton....they are great), it got plumbed in so that I have double the tank capacity (no check valves). The cheapo is set to start 20 psi below the main one in case it fails. It hasn't ever come on except to test once a year.

How long would it run if needed? My guess....not very long. Who knows? It LOOKS brand new....but running nonstop 15 hours a day can't be good for it.....eh?

Plumb the tanks together, and save cycles on your main unit. (And if some car wash guy tries to sell you a cheapo air compressor that looks brand new.....don't buy it!)
 

MEP001

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I had the same thing happen, came in Friday eveing and the compressor motor had burned up. The only thing it ran (at the time) was the foam frush air, so I took my 12V compressor and battery charger out of my trunk and wired them up together through the compressor's switch. It actually worked and lasted until Monday evening when I could get back with a motor - the little compressor was completely seized, but there was still enough air in the tank to last until I got the motor replaced.
 
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