Do I need a 1way valve

red hilux

Well-Known Member
I’m not sure if it’s needed or not

I know you do need it for bigger air tanks. But I’m only installing a 2.2 liter air tank to an ARB twin head compressor.

I asked someone at arb once. They said yes. But at the same time, I can’t see a 1way valve on their twin head with air tank compressor. Is that a do as I say and not as I do thing?


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Big compressors you need one and the bigger compressors have unloader valves so the motor can spin up to speed before they start pushing full pressure. They are also pushing a lot more cc's with much bigger pistons and lower RPM than a small 12V job.

I built my compressor in a box with a 2L air tank and no one way valve and it goes well. The compressor has no issue starting with 110psi in the holding tank When you think about it, its no difference to switching off the compressor to check the gauge and then flicking it on again


Well-Known Member
So the compressor pumps air into a positive pressure

Once it stops the system can relief back to atompheric, if there is no check valve that system is always pressurised will that hold over time

If having air in the tank all the time is not important well I guess it's not important to have a check valve

If it is only a small tank I guess it's not that important More important is keeping the water to a minimum


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I wouldn't see any real need for one on a single compressor I've been running my 14yr old Bushranger Max air into an air tank most of it's life with a 120psi relief valve on the tank which helps get rid of water in the tank and without a one way valve near the compressor. I haven't noticed any harm done to the compressor but yes the tank will loose pressure during the day.

Recently I fitted a second compressor as a back up via a T-piece I put one way valves on both air compressors it's wired up so only one can be turned on at a time. The air tank is now holding pressure it will be down to about 40psi after 2 days which is ok so less work to get it back up.
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Depending on your set up if you have a cut of pressure valve all good but if a pressure release valve like my set up you will have to be reasonably quick moving between tyres with a twin head compressor a larger 6ltr or similar would be a better size if you have room.


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Just curious because I am upgrading my air compressor and have been thinking about an air tank but 2.2l of air (a little bit bigger than a coke bottle) didn't strike me as being of much advantage. Having one of those 240v compressors with the frame as an air tank it only ever gives me about 2 shots with the framing nail gun before the compressor kicks in so I was wondering what advantages there might be to having a tank given i don't have much room for one.


Active Member
If you have a small air tank witch fills fully up between changing from 1 tire stem to another tire stem it would be beneficial. if you have a biggish air tank you have to fill up the volume of the air tank first to build up some air pressure and then tire the tire will depressure the air tank , so then you will be pumping the air tank and tire at the same time. You will have to pump more air overall, the only benefit form a big air tank is if you prechage it for the first tire and air tools.


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I currently have an 18ltr tank which is a bit big for my compressors previously I had a 6ltr which was better and I reckon I was able to pump the tyres up faster because I didn't have to wait long for it to fill up between tyres. The only other real benefit of the larger tank is the storage capacity I can turn the compressor off when the tank is full and have enough air to top up the tyres on my wife's car which usually takes a few pounds each. Next time I will go back to a smaller tank and get an alloy one not steel.


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Ive seen old fire extinguishers, gas cylinders, even rock sliders used to store compresed air. Extra air for only a lilttle extra work is always handy.


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If you are pumping up a tubless tyre and its off the bead, you need a blast of air to get it seated enough to seal
I've gone through that process a few times and believe it or not the compressor hooked directly to the tyre helps me best. I manipulate (bear hug) the tyre and as soon as it seals the compressor will speed up and you know to stay still for a bit until the pressure builds and then clear out until the bead seats. The compressor does the rest. I see your point but I'd suspect that usually the plenum would just run out of pressure while you fiddle around trying to get the seal and then you won't have instant back pressure to know when you have the seal? Just a thought.