N/A Moisture in PCP airguns

My YH pumps to a scba tank. The first filter is the centrifugal type mounted vertical. The second filter is a small desiccant cartridge and the third is the little cotton filter that came with the YH. I periodically will empty the scba bottle and I have never seen any moisture and it acts as the last chance filter because I figure any moisture if present should condense out in the scba bottle. I use a 3450 psi scuba tank store filled to refill the scba and then pump to 4500 psi with the YH after the water inspection. Since I have never seen moisture in my scba bottle I may dispense with the occasional drain down for inspection.
 
snarky remark, there is a certain politician that thinks it does. That out of the way, how about molecular sieves? I run a tampon (foam cylinder, into....nary a clue because I can't get it apart, then into a molecular sieve. But I'm in a relatively low/mid humidity area about 46% currently.

I know! He's our gubbenor! 🤣😅😆😁
 
if you are not using one of these and you have an expensive air gun, you're crazy.
the air going into your gun should be clean an dry you have to dry it after it's already been compressed.

I would advise getting one of these.


Thanks for the mental health assessment.

I'm good, thanks...
 
I didn't read everything so if I repeat something, I apologize ahead.

First, and this may be controversial, ... but I am not a fan of squirting anything, even silicone oil, in the gun in the hopes that it will do any good. The tiny amount of lube you should use during a rebuild is all that needs to be in there. Just my opinion over many years of pcp use and building.

To control moisture, you first need to make sure than your fill line, filter, and anything else in line on the way to the gun should be below the gun during the fill process. This keeps moisture from rising up into your gun. Cotton filters do help by blocking liquid flow. So they do help some. Also your environment needs to be fairly low RH, ie 50% or less, so a dehumidifier might help in the room where you fill. Also, pump for short intervals, less than 10-15 minutes and then vent the lines.

If you use a pump that is conducive to it, and you just can't get the moisture out, the real solution is to feed your compressor nitrogen at low pressure. It's not at all expensive and is the magic bullet for moisture problems. All you need is a way to pipe a line from a 40 cu/ft N2 cylinder with a cheap regulator to you compressor, run it at 5-10 psi and done, NO MOISTURE.

I live in WV and it can get hot and humid in the summer, and I fill in my garage, which is usually open to the outside most of the time. If I'm careful, I get no moisture in the gun and only a small amount in the compressor and lines. The fittings do runs a bit inside the fill line and block, but never gets to the gun.

One important thing is that you should open EVERY pcp cylinder on a, I don't know, yearly basis to inspect the inside for corrosion. This is the best way to KNOW if you have a problem.

I have used Nitrogen for about a year now and will never go back. No filters, (except for a cotton debri filter) and no maintenance to mitigate moisture. It alleviates all the hassle of filling pcp rifles. If you count the cost of changing the moisture absorbing media as often as you really should, N2 looks pretty good price wise.
 
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You might have a compressor for nail guns car tires spray paint ETC and noticed the drain valve on the tank. Here in south Florida its very humid and even a smaller tank compressor builds up a good amount of water at 120lbs psi. I am also a scuba diver and if the air wasn't filtered you might catch pneumonia from breathing it. I don't know the long-term effects on a pellet gun but for a couple dollars more I don't risk it.
 
I didn't read everything so if I repeat something, I apologize ahead.

First, and this may be controversial, ... but I am not a fan of squirting anything, even silicone oil, in the gun in the hopes that it will do any good. The tiny amount of lube you should use during a rebuild is all that needs to be in there. Just my opinion over many years of pcp use and building.

To control moisture, you first need to make sure than your fill line, filter, and anything else in line on the way to the gun should be below the gun during the fill process. This keeps moisture from rising up into your gun. Cotton filters do help by blocking liquid flow. So they do help some. Also your environment needs to be fairly low RH, ie 50% or less, so a dehumidifier might help in the room where you fill. Also, pump for short intervals, less than 10-15 minutes and then vent the lines.

If you use a pump that is conducive to it, and you just can't get the moisture out, the real solution is to feed your compressor nitrogen at low pressure. It's not at all expensive and is the magic bullet for moisture problems. All you need is a way to pipe a line from a 40 cu/ft N2 cylinder with a cheap regulator to you compressor, run it at 5-10 psi and done, NO MOISTURE.

I live in WV and it can get hot and humid in the summer, and I fill in my garage, which is usually open to the outside most of the time. If I'm careful, I get no moisture in the gun and only a small amount in the compressor and lines. The fittings do runs a bit inside the fill line and block, but never gets to the gun.

One important thing is that you should open EVERY pcp cylinder on a, I don't know, yearly basis to inspect the inside for corrosion. This is the best way to KNOW if you have a problem.

I have used Nitrogen for about a year now and will never go back. No filters, (except for a cotton debri filter) and no maintenance to mitigate moisture. It alleviates all the hassle of filling pcp rifles. If you count the cost of changing the moisture absorbing media as often as you really should, N2 looks pretty good price wise.
Thanks for the pointers. Your not to far away from me. I’m across the river in Ohio. Little town by St. Clairsville OH about 15 mins from Wheeling WV.
I bought that RTI compact from martin if he mentioned me.(thinking you right guy haha)

Take care
Rib
 
if you are not using one of these and you have an expensive air gun, you're crazy.
the air going into your gun should be clean an dry you have to dry it after it's already been compressed.

I would advise getting one of these.

Interesting video. I fill a very large 109 cu/ft C/F bottle to fill my guns, I generally top off the tank at about 225bar aprox 3300psi and don't open my bottle until the compressor has reached that pressure ensuring the medium is adequately pressurized before letting the air pass by into the bottle.
 
Rookie question, if you use a compressor to fill a 6.8L tank, once the tank cool down, the water should settle and collect at the bottom of the tank right? if you keep the bottle upright when you refill your PCP, does it mean only dry air would get pumped into the gun? can those water inside the tank still somehow get transfer into the PCP during refill?
 
It seems to me once the moisture media is wet it will need to be removed from the housing to dry out . Otherwise it will just stay wet . I like the idea of the water separator before the filter like the video above . My little cs2 doesn't get hot when doing direct fills, mostly indoors and my PCP's are 18" or so above the compressor and using 2 smaller filters . Then I run the compressor around 5 seconds with the valve open to blow out any drops .I haven't noticed any moisture making it to my airguns . Great information and explanations.
 
Rookie question, if you use a compressor to fill a 6.8L tank, once the tank cool down, the water should settle and collect at the bottom of the tank right? if you keep the bottle upright when you refill your PCP, does it mean only dry air would get pumped into the gun? can those water inside the tank still somehow get transfer into the PCP during refill?
I can only assume the water would stay on the bottom. Skip the rest of my post as it could be incorrect
 
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Most scba and scuba tanks have a dip tube to prevent FOD from clogging the valve if upside down. Turning such a tank upside down to expell water will therefore not work unless it is enough to be above the dip tube. Which would be a whole bunch.

During the fill cycle, several times, I will purge the compressor by opening the high and low side drains momentarily to blow the accumulated moisture out before it even gets to my filters.
 
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Most scba and scuba tanks have a dip tube to prevent FOD from clogging the valve if upside down. Turning such a tank upside down to expell water will therefore not work unless it is enough to be above the dip tube. Which would be a whole bunch.

During the fill cycle, several times, i will purge the compressor by opening the high and low side drains momentarily to blow the accumulated moisture out before it even gets to my filters.
I wasnt sure the PCP tanks have that tube? Mine is for scuba and does have it although it is removable as its just like a straw conected to the DIN valve. Great point though!
 
Any valves used for a life support system, scba or scuba, are going to have a dip tube. This tube usually screws in but is sometimes pressed in.



Inverting a tank equipped with such a valve will not vent water out. I do not know if purpose made paint ball or PCP cylinders and valves are so equipped but I suspect they are if for no reason but to prevent FOD from clogging the valve, the air lines or your gun.
 
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I ordered a 6.8L tank from Amazon, still waiting for it but the valve doesn't have any extended tubing or stem, looks like i could just turn it upside down to purge any water collected in there if necessary, have the CS4 coming at the same time to fill this thing.

My thought process was that the tank will be used as a main moisture collector and heat-dump reservoir, once the tank is completely cooled down, the air being pumped into PCP gun from the tank will be dry and cool, it should theoretically contains less moisture once the water settled at the bottom of the tank, and having an inline moisture collector wouldn't be as big of a deal or even necessary since the tank will be collecting moisture instead, one less thing to maintain. Another reason for getting the tank is so i can bring it to the range instead of compressor.


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I ordered a 6.8L tank from Amazon, still waiting for it but the valve doesn't have any extended tubing or stem, looks like i could just turn it upside down to purge any water collected in there if necessary, have the CS4 coming at the same time to fill this thing.

My thought process was that the tank will be used as a main moisture collector and heat-dump reservoir, once the tank is completely cooled down, the air being pumped into PCP gun from the tank will be dry and cool, it should theoretically contains less moisture once the water settled at the bottom of the tank, and having an inline moisture collector wouldn't be as big of a deal or even necessary since the tank will be collecting moisture instead, one less thing to maintain. Another reason for getting the tank is so i can bring it to the range instead of compressor.


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Makes sense because these paintball/PCP valves are not a part of a life support equipment.