Welcome! Please use the navigational links to explore our website.
PartsASAP LogoCompany Logo Auction Link (800) 853-2651

Shop Now

   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver

Tool Talk Discussion Forum

Running dual air compressors

Welcome Guest, Log in or Register
Author 
1952henry

02-20-2007 07:08:22




Report to Moderator

I have two identical Sears 2HP, 7 cfm compressors. Both are 220v. How can I run them together so neither has to work too hard when I bead blast? I don't want both to click on at the same time. Thanks.




[Log in to Reply]   [No Email]
1952henry

02-21-2007 05:36:40




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 07:08:22  
Thanks one and all for your help/ideas!



[Log in to Reply]  [No Email]
Charles (in GA)

02-20-2007 18:10:32




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 07:08:22  
Old has the best idea, use check valves on both compressor tank outlets so that air can leave the tank but not enter. This will allow the two compressors to operate totally independent of each other. You may still have to tweak one of the pressure switches slightly to keep the pumps from switching on at the same time, but a couple of pounds difference is all you will need, and I doubt both compressors will be that close anyhow.

Why not sell both units and buy one decent compressor. A bead blast cabinet will require all the air both units will put out, a good 5 hp two stage shop compressor will do you much better in the long run. I realize there is a $$$$ factor in this decision however.

Charles

[Log in to Reply]  [No Email]
1952henry

02-20-2007 18:26:13




Report to Moderator
 Re: Running dual air compressors in reply to Charles (in GA), 02-20-2007 18:10:32  
Space is also a premium, my blasting setup is small, and the second compressor was free. Where does one get a check valve?



[Log in to Reply]  [No Email]
XRogerX

02-20-2007 22:34:42




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 18:26:13  
You do not need a check valve if the highest cut-out pressure is below the safe working pressure of the lowest rated tank and its safety valve. There is already a check valve between each pump and its tank, so you will not hurt anything by simply joining them with a tee, provided the highest pressure does not exceed the specs of the lowest rated tank and relief valve.



[Log in to Reply]  [No Email]
Bob

02-20-2007 18:59:33




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 18:26:13  
The ONLY reason to use a check valve would be if the pressure rating of one tank is not up to the level of the others, and you don't want to other compressors to "backfeed" into that tank.

Otherwise, just "TEE" the darned things together and they'll work JUST FINE.

NO need to make this any more complicated than it needs to be!



[Log in to Reply]  [No Email]
1952henry

02-20-2007 19:20:37




Report to Moderator
 Re: Running dual air compressors in reply to Bob, 02-20-2007 18:59:33  
I appreciate the feedback, and am still curious what type of check valve may be needed.



[Log in to Reply]  [No Email]
Bob

02-20-2007 19:33:41




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 19:20:37  
If you REALLY want to use a check valve, Grainger is one source for "in-line" air check valves.



[Log in to Reply]  [No Email]
1952henry

02-20-2007 19:57:42




Report to Moderator
 Re: Running dual air compressors in reply to Bob, 02-20-2007 19:33:41  
Now, how do you set the pressure switch?



[Log in to Reply]  [No Email]
evielboweviel

02-21-2007 04:15:21




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 19:57:42  
alot of the bigger ones are adj just like on a water well tank. take the cover off and srew the nut tighter to raise presuure and loosen to drop pressure
Ron



[Log in to Reply]  [No Email]
Bus Driver

02-20-2007 13:13:19




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 07:08:22  
Sure. Back in the late 1950's, I used two small compressors feeding into one 80 gallon tank. For one of the compressors I had no motor big enough to drive it. So one of the compressors had two motors belted together, one had it's own motor. One tank, two compressors, three motors. One pressure switch controlling a relay to handle the current. Limited budgets call for imagination. I happen to know that it still works fine.

[Log in to Reply]  [No Email]
XRogerX

02-20-2007 09:42:20




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 07:08:22  
You have to set one compressor up so that its operating range is outside the other. One machine can be set up to run 80 - 125 and the other can be set to run 90 - 115 or something like that. One machine will cut in at the higher pressure and run until the pressure drops to the cut-in of the second machine. The second machine will run "inside" the range of the first machine, cutting in and out while the first is running. This will allow it to meet air demand under heavy load. If you wanted to switch lead and lag machines, you could plumb the switches remotely with copper lines and valves to change which compressor feeds which switch, to even out wear on both machines.

[Log in to Reply]  [No Email]
old

02-20-2007 09:31:30




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 07:08:22  
You can hook them up with a tee in the line but you will also need check valves in the lines before the tee but after the compressor of the stronger one will back feed the weaker one and could damage the weaker one



[Log in to Reply]  [No Email]
ebbsspeed

02-20-2007 07:41:12




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 07:08:22  
You might have to tweak the pressure switches a bit in order make sure they don't kick on at the same time.



[Log in to Reply]  [No Email]
Wild Bill

02-20-2007 07:26:53




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 07:08:22  
Connect the compressors with tees in the lines, all there is to it.



[Log in to Reply]  [No Email]
Allan In NE

02-20-2007 07:17:19




Report to Moderator
 Re: Running dual air compressors in reply to 1952henry, 02-20-2007 07:08:22  
Sure,

The last garage I worked at had four of the rascals tied together. Later swapped out for two bigger units.

Allan



[Log in to Reply]  [No Email]
1952henry

02-20-2007 17:56:19




Report to Moderator
 Re: Running dual air compressors in reply to Allan In NE, 02-20-2007 07:17:19  
Thanks to all for the help. Now, how does one set the pressure switches?



[Log in to Reply]  [No Email]
[Options]  [Printer Friendly]  [Posting Help]  [Return to Forum]   [Log in to Reply]

Hop to:


TRACTOR PARTS TRACTOR MANUALS
We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]

Home  |  Forums


Copyright © 1997-2023 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters

Website Accessibility Policy