I dont use a filter on any of my compressors , just feed them nitrogen no need for moisture or oxygen in my guns
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what water filters are you using on your GX (cs4) compressor ?
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I am definitely not a subject matter expert on filters or compressors ....That being said, I put my 3rd stage (molecular sieve filter) vertically as a final preventative measure of moisture build up especially with the YH compressor. I haven't had any moisture in that filter after filling a 30 min SCBA in stages. I have had moisture drain off from the 2nd stage filter (centrifugal? type filter). I have not tried this on the GSX4 yet. Honestly, I think this set up would be overkill given the efficiency of the GSX4.
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Give it time, and you will have issues . . . .
The air leaving the compressor is hotter than ambient, and by definition will be at 100% relative humidity. As the temperature of that air charge cools down in the tank, water vapor will condense out. Granted, for any one fill it is not much water, but it will build up over time.
Use a desiccant filter to capture that water vapor and you won't have any issues, at least from water.
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I change valves often (at least monthly) switching between paintball and PCP. I have not had any water issues in my air bottle. For my little paintball tank... it has been a non-issue. Those big tanks may be another story altogether.
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I am new to the PCP game having been using springers. Major surgery has put me in a postion of not being able to cock them for 4-6 months. I don't hunt and do most shotting in my back yard so I went with the CS3-1 compressor because I don't think that I will be doing much with a tank-but may go to joing a club at some point.
I just retired from the art and antique restoration business and built classic cars for a happy doing my own body work and paint. No longer doing that but I built a systen that had 60ft of pipe before it went to a 3 stage filter to take water out of the system and produce clean dry air..
All of the filters had drains. I used spray guns and air brushes and never had an issue with moisture or oil.
I know that this is a complety different situation but as I got to thinking about it all I found this forum.. I canot see using a filter without a drain so I was looking at the Bakon at $99.99 but you cannot change the filter material, and as as another member wrote will the centrifugal filtration process work for us. The other unit is from TOAUTO for $138. As I read reviews all of them show some problems with leakage, fitting not fitting corectly ETC.
I picked up and air Venturi X with 2 other barrels as my first PCP (as an Xmas present from my wife-but she will not give it to me any earlier)
Any thoughts as to what filter to use beyond these?
Thx Abe
I just retired from the art and antique restoration business and built classic cars for a happy doing my own body work and paint. No longer doing that but I built a systen that had 60ft of pipe before it went to a 3 stage filter to take water out of the system and produce clean dry air..
All of the filters had drains. I used spray guns and air brushes and never had an issue with moisture or oil.
I know that this is a complety different situation but as I got to thinking about it all I found this forum.. I canot see using a filter without a drain so I was looking at the Bakon at $99.99 but you cannot change the filter material, and as as another member wrote will the centrifugal filtration process work for us. The other unit is from TOAUTO for $138. As I read reviews all of them show some problems with leakage, fitting not fitting corectly ETC.
I picked up and air Venturi X with 2 other barrels as my first PCP (as an Xmas present from my wife-but she will not give it to me any earlier)
Any thoughts as to what filter to use beyond these?
Thx Abe
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I would advise mounting a filter vertically to allow gravity to act as an assist for the beads to work. If you reach a point were water is collecting in the bottom of the filter the beads are no longer effective. Molecular sieve only holds about 20% of it's weight in water vapor. Those gold filters are repackable and you should monitor them by the number of hours run. Beads dripping water means you're long past their saturation point. Even the more expensive filters that have drain valves at the bottom should never spray moisture. That means the pre filters built into the compressor have either not been opened frequently enough during a fill or isn't properly designed for that compressor's output. The compressor bleed should discharge most of the moisture during a run. The desiccant filter should be for the small amount of moisture that gets past the internal moisture drain.
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From what I have read the air in the filter needs to be over a certain amount of pressure/psi before the molecular sieve can function properly and remove moisture, that being said I suppose if your guns bottle pressure is high enough before you top it off it should allow the pressure in the filter to build before it passes through the check valve on the gun.
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Exactly. That's why compressor designs using molecular sieve filter on the air intake is purely window dressing and useless. The Tuxing T033 is an example with one. Marketing and an ineffective intake filter. It would work slightly better with colored gel beads designed for low pressure moisture filtration.
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This is not exactly true, at least from a physics standpoint. Molecular sieve will adsorb water vapor out the air just fine at atmospheric pressure - just leave some out uncovered and you will find that it will become fully saturated and useless as a desiccant fairly quickly - in anywhere from a hours to a few days, depending on the RH of the air, and how it is exposed to that air.
In practice, what @Humdinger wrote is completely true, but not because of the media itself. It is because most filters are not properly designed for the application.
The issue is from the functional interaction of two factors: the first that ambient air contains massively more water vapor in it than it will have after compression (that is why we have to vent so much liquid water out with most compressor set ups), and the second is that relative flow rates of the air stream are vastly different at the two different pressures. Since we are dealing with the same amount of air (in terms of molecules of air) before and after compression, the difference in the density of the air, and thus the speed of the stream as it flow, in roughly equal to the difference in pressure in terms of absolute bar of the air - so at 300 bar, the input stream is moving roughly 300 times "faster" than at output.
One can thoroughly dry air with molecular sieve before it enters a powered compressor, but the filter would need to be very long (to support a long enough dwell time) and have a lot of desiccant in it. Picture a five foot long 2" diameter PVC pipe that the air is drawn through before compression - this would probably work very well, but would be prohibitively expensive in terms of amount of desiccant used and the relatively short "lifespan" of it before it becomes saturated (probably faster than a properly sized post-compression filter). If one wanted to do this, it would be best to use easily rechargable media - most likely silica gel beads.
I do feel that the molecular sieve air driers used on some hand pumps - like the Hill "Drypac" units - can work very well, but they are subject to rapid degradation of the media from the moisture in the ambient air. The fact that they don't have indicating beads in them makes it worse - I think most people waste money with these if they are not taking steps to extend the life of the media. When I used to use one I would take the filter off the pump and store it in a ziploc bag between uses to extend the life some.
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The drypack refills now come with a package of indicating beads which you are supposed to put on top of the media. I noticed it when looking into Hill pumps.
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