DanC
Well-known member
How do I add an aux. tank to my present air compressor? I have a 60 gallon now and found a good 30 gallon tank I want to use to add alittle capacity. Where do I put my pressure switch and things like that?? thanks-
auxillary air tank-
- Thread starter DanC
- Start date
D KRAGER
Well-known member
Leave the pressure switch they way it is on the current compressor. Just tee in the other tank anywhere, doesn't really matter. Just make sure to put a valve on it in case you don't want to use it. At work we have an 80 gl tank, plus when we are using the automated air system we have an old 300 gl LP tank plumbed into the line we can use also.
russlaferrera
Well-known member
Why the extra capacity? Remember it will take longer to fill to cut off pressure.
kvom
Well-known member
A 90 gallon tank is better than a 60 for the same reason that an 80 is better than a 60.
If you are running a tool at 100psi and the switch turns the pump on at 110, then you will have 100psi longer (this assumes that tool uses more air than the compressor provides).
BrianAltenhofel
Well-known member
Also, if adding auxillary tanks, key an eye on the motor to watch out for excess heat while filling all your tanks. I had a buddy that tried to fill 8 30 gallon tanks AND the 60 gallon that was on his compressor (all from empty). It ended up burning up. So, there's a good reason to put valves on your auxillary tanks.
PAToyota
Well-known member
There is a lengthy discussion already posted on this topic here: http://www.garagejournal.com/forum/showthread.php?t=16952
russlaferrera
Well-known member
Sorry, I fail to see your point. Air tools require an air output of ? PSI X ? CFM to operate. An example, A 1 gallon tank would have the required PSI but not have the required CFM to operate a impact wrench.
A 100 gallon tank would have the CFM but when the PSI goes down you have to wait a longer time to return to the correct PSI to operate. Bigger tank, bigger wait.
To correct this, the ONLY way is to get a LARGER compressor.
Steve in Mi
Well-known member
If there wasn't a need for extra capacity (a tank) none of your compressors would have them. Smaller and some big lower end compressors do sometimes have a duty cycle usually associated with the motor used. I've owned many compressors and all were continuous duty - I wouldn't consider anything less. So if we get beyond duty cycle what are the pluses for increased capacity. Potential for less motor starts (spiked amps) therefore lower power consumption - save some money. Longer uninterrupted periods of use. If you do not see the advantage to either of these two ... then ... you don't need more capacity - stick with what you have. Those that see the need, yes, more tank volume will help.
nissan_crawler
Well-known member
I'll argue that. A pump puts out what a pump can put out, period. Hell, you could put a 1,0000 gallon tank on a 10 cfm compressor, and it would take forever for it to run down, but once it did, you would go gray waiting for it to pressure back up. Adding a 30 gallon tank does ONLY one thing. It makes the run AND wait times longer, that's it, nothing more. In the end, it all works out the same.
D KRAGER
Well-known member
Where the extra tank helps is when you are using more air for short intervals than the compressor can put out.
We have an automated chemical plant at work. All valves and some of the small pumps use air. When you are loading a truck it takes lots of air, more cfm than the comressor can put out. Then there are breaks between loads, this lets the compressor catch back up for the next load.
So if you can't consume more air than the compressor puts out, then the extra tank most likely won't really help you much.
We have an automated chemical plant at work. All valves and some of the small pumps use air. When you are loading a truck it takes lots of air, more cfm than the comressor can put out. Then there are breaks between loads, this lets the compressor catch back up for the next load.
So if you can't consume more air than the compressor puts out, then the extra tank most likely won't really help you much.
Steve in Mi
Well-known member
Okay but you would be wrong.
Forget the size of the pump, the uninterrupted time of use is greater for a big tank of air versus a small tank of air.
It takes longer to drain them and longer to fill them. Kind of like the difference between a 12 oz bottle and a quart bottle.
Big air uses, like sand blasting, need a lot of air, so a big storage area is a good idea. You don’t have to stop working and wait for the compressor to catch up to you. It will do that when you stop to move stuff around, take a break, or whatever.
Do check your motor for running hot since it will be running longer than the factory guys thought. It may not hurt to hook up a small fan in parallel to it to run some air over it.
Big air uses, like sand blasting, need a lot of air, so a big storage area is a good idea. You don’t have to stop working and wait for the compressor to catch up to you. It will do that when you stop to move stuff around, take a break, or whatever.
Do check your motor for running hot since it will be running longer than the factory guys thought. It may not hurt to hook up a small fan in parallel to it to run some air over it.
russlaferrera
Well-known member
I see your point. So if you get a 1hp compressor with a 600 gallon tank and run it a night it will last until quitting time. That is a great idea. This way the cost of a larger compressor will not be issue, plus it will be much quieter.
Thank you! I was thinking of buying a 7 1/2 hp compressor as i need more air. Instead, just buy a much larger tank.
russlaferrera
Well-known member
This works because it cover the "Peak Demand" and there is sufficient recovery time.
Is a shop or industrial setting where air is needed constantly to perform the tasks...who is going to wait for air pressure to recover. Ya, tell a painter or body man "sweep the floor or take a break while the air builds up"
A homeowner, OK he can wait. A pro, don't even think about it!
Steve in Mi
Well-known member
russlaferrera This thread has nothing to do with pump capacity (except what has been interject to perhaps hi-jack the thread to someone elses objective). The compressor pump is what he already has (a given) and the question was about how to and if adding another tank would add to his capacity. The first part was answered early on and the second part was confussed by other issues but the correct answer remains, YES it will.
A bigger compressor (more CFM) would also add to capacity for a given tank size. But, that's another thread - not this one. If what you take away from this is you need a 1 HP compressor and a 600 gal. tank - so-be-it. Be sure to post pictures.
A bigger compressor (more CFM) would also add to capacity for a given tank size. But, that's another thread - not this one. If what you take away from this is you need a 1 HP compressor and a 600 gal. tank - so-be-it. Be sure to post pictures.
russlaferrera
Well-known member
I was being pricky. Other than peak demand vs. compressor output a 2nd tank is of no use. My statement illustrates this. The extra run time you get with a larger tank(s) will be lost when the tank is refilled. Do the math!
Look at my statement , then reverse it. A large compressor will always keep the tank full. Why? VOLUME. AIR has a means of measurement . It is Cubic feet per minute, then you pressurize it Pounds per square inch.
Now about a 1 horsepower compressor and a 600 gal tank. It would work. It IMO would be very impractical. IMO as impractical as me paying a bunch of people standing around waiting for a compressor to fill a tank (s) up.
The bottom line.... Use the proper tool to get the job done. Yes we all have to improvise at times, and we all have to upgrade our equipment when the need is justified. BS is BS!
Bib Overalls
Well-known member
I have a compressor with a 60 gallon tank and a second 60 gallon tank that I will be plumbing in sequence. Based on my experience to date I know that additional capacity will help when I am using high demand tools. I am plumbing them in sequence because I want the air to cool in the second tank and shed water before it enters my air lines. We have a lot of humidity here and even with a moisture seperator a lot of water gets through. Anything wrong with my thinking?
nissan_crawler
Well-known member
You're apparently referring per cycle, which doesn't mean jack.
Until the pump has to kick in, then you have to wait for pressure for just as long as it took to decrease. In other words, pointless.
Let's say a 5 minute span
30 gallon tank:
30 seconds use
15 seconds run
this give you 7 use sessions and 6 run sessions, which equates to 210 seconds use, 90 seconds run
60 gallon tank
1 minute use
30 seconds run
that gives you 3.5 use sessions, and 3 run sessions, which equates to 210 seconds ue, 90 seconds run.
OMG, the same thing!! who would have known
The ONLY thing adding capacity changes is LENGTH of run and use time for ONE CYCLE. Overall time will be the exact same.
This is the exact reason I have a pump that will do 18 cfm @110 p.s.i. on a 30 gallon tank. For low use, it'll run off the pressure switch, for high demand, it'll run continuously with the head unloaders.
One could actually argue that extending the run times will allow it to heat up and reduce longevity.
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Maulerman
Active member
It has been entertaining listening to you all bicker. May I interject? When adding an additional air tank be sure to double and triple check that all connections are leak free or else you are defeating the purpose. The factories go to great lengths to ensure no leakage. Leakage costs $
nissan_crawler
Well-known member
A GOOD water separator will do more than that 60 gallon tank will.
The end result of exceeding the duty cycle is something is going to get tired & give up. How long was your buddy able to run it this way before it burned up or was it right after he added all those tanks? It's much better to do like nissan_crawler did and have a large pump/small tank than an undersize pump/huge tank. Think 427 engine in 2000 lb car vs 3.8 V-6 in full size school bus, which will be more fun to have & use & which will last longer?