Using two air compressors at same time?

[Scott Gardner]

I'm using a Sears 6hp/33 gallon single-stage compressor right now, and it's fine for small jobs like motocycle parts.</cr>
What I'd like to know is whether it would be possible to hook up a second identical compressor to my plumbing to increase capacity? My shop is plumbed with one-inch black iron gas pipe. I leave the outflow regulator on the compressor all the way open, since I have individual regulators at each tool drop. I would replace the compressor with a larger one, but the one I have is almost new, and adding a second identical one would be cheaper than getting a bigger one, even if I sold the one I have for most of what it cost me. I'm curious about the pros and cons, since I don't recall ever seeing two compressors attached to a single plumbing system. </cr>
Thanks,</cr>
Scott Gardner

 

[Motornoggin]

I usually run only one main comprsssor, but if I need a lot of air for something ( like sandblasting), I have three compressors all plumbed in and ready to fire up. Two five horse and a 1 1/2 horse. I use all three tanks with the main compressor, but can fire the others individually if needed. Works fine, no issues that I'm aware of. It is very dry where I live, so I don't have much of a condensation problem. I don't know if multiples will help or hurt.

 

[rex]

Sure you can do it,some shops set up this way.The single stage pump is always going to limit your abilities though.If you hook in another you'll have a holding tank to double your air supply,but I really don't know much about it beyond this point.I don't know if they should both run together or have one as the main and the other as a kicker to help the first when you really start sucking up the air.If you're serious about using air in volume,Usually Home Depot and Sams gets a run of 7.5 hp 80 gal tanks for $900 or less.The Craftsman single stages aren't bad at all,but if you're going to really use them they'll probably be short lived.

 

[Scott Gardner]

How do you get the other two compressors to start running? I was afraid that if I added a second compressor, the motor in one compresser would always start running first as the overall system pressure dropped, even if they were both the same make and model. This would pressurize both tanks, so the motor in the other compressor would theoretically never run. How do you manually start the motor in the compressor that has the lower-activating pressure switch?</cr>
Scott

 

[Ronnie C.]

I work in the natural gas industry, and have had to deal with such problems in the past. In our process plants, we have 2 air compressors to handle all the control systems in the plant. One is set to kick on at 90 lbs, the other one is set to kick on at 80 lbs. Both are plumbed into the same line . By adjusting your air pressure switch on each compressor this way, you will use compressor # 1 untill your air usage demand out runs what comp.#1 can put out, then comp.#2 will kick on automaticly when air pressure drops to 80 lbs..Both air compressers can be set to kick off at about the same time. I hope I did not confuse everything.

 

[hdchuck]

I am a beginner myself but I am reading a book by Jos Kosmoski ( not sure on spelling ) the House of Kolor founder and he recommends exactly what ronnie says. An additional benefit is that if 1 compressor goes down you are not out of business.

Chuck