Do you pickle your filter media?

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maniago

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After a couple of days of not using the compressor, I see that my filter stack has returned to ambient pressure. Its well isolated with a check valve and BPR on either end, but the leaks are too small to find with soapy water, so I guess this is something I have to live with. The rest of the compressor stages also eventually bleed down.

If your compressor is going to sit at atmosphere for a significant period of time, do you take out your filter media and store away so it isn't "exposed"?

Or is this just not an issue as the media (ie MS) does its real magic only under pressure and any ambient loss is minor?

I'm not really sure this has any significant effect wrt to Hop or AC, but if so I'd like hear about it.

Thanks for any thoughts!
 
After a couple of days of not using the compressor, I see that my filter stack has returned to ambient pressure. Its well isolated with a check valve and BPR on either end, but the leaks are too small to find with soapy water, so I guess this is something I have to live with. The rest of the compressor stages also eventually bleed down.

If your compressor is going to sit at atmosphere for a significant period of time, do you take out your filter media and store away so it isn't "exposed"?

Or is this just not an issue as the media (ie MS) does its real magic only under pressure and any ambient loss is minor?

I'm not really sure this has any significant effect wrt to Hop or AC, but if so I'd like hear about it.

Thanks for any thoughts!


I have a small leak in my system that was the bain of my existence for a long time. No matter what I did I couldn't stop it. I was at the point of almost buying stainless tubing and all of the accessories instead of high pressure hose(which I set up that way because I wasn't originally sure how I wanted to whole system mounted). I even bought the oxygen compatible sealing paste and was going to pull the whole thing apart and fix it that way, but it's just not worth it. Originally I thought it was dropping my pressure in my stack too, so I called Lawrence Factor and basically was told at my level of use of my fill station the loss of efficacy by staying at ambient pressure wasn't worth the headache fo worrying about it. I'm changing my filters way before end of life anyway.
 
Originally I thought it was dropping my pressure in my stack too, so I called Lawrence Factor and basically was told at my level of use of my fill station the loss of efficacy by staying at ambient pressure wasn't worth the headache fo worrying about it. I'm changing my filters way before end of life anyway.

So how much (time and volume per week) do you use your compressor and how long before your filter drops to ambient after you stop?

For me, at most, mine will be on for about ~6hrs and ~ 700cuft/week. I sure don't want to be changing out media every other week. That seems like a waste, but it'll be what it'll be I suppose....
 
So how much (time and volume per week) do you use your compressor and how long before your filter drops to ambient after you stop?

For me, at most, mine will be on for about ~6hrs and ~ 700cuft/week. I sure don't want to be changing out media every other week. That seems like a waste, but it'll be what it'll be I suppose....
I typically fill four sets of double 85s and two stages every week to two weeks. Like I said I thought the filter was draining too but it's behind a check valve so only the system from the fill panel to the priority valve leaks. It takes about 24 hours to drain. Even if it did drain the filter after all, LF said it wasn't a huge deal.
 
If you have a check valve upstream and a back-pressure valve on the downstream side of the filter appliance it should not leak down to ambient pressure unless you have a leak or are leaving the system for a couple weeks with no use. I'd have a look first at the check valve by pressurizing the system then shut it down and loosen the intake fitting on your final separator. If that check valve is leaking you will detect the leak using soapy water. We can leave our systems for a month without use and it will still hold pressure albeit only to about 1000 psig.

If no leak there then likely your BPV is leaking down in the forward direction. We have had problems with this before which was solved by either rebuilding the valve or purchasing a different brand of valve. If you search the forum you'll see a thread on this I believe from a year or two ago where it appeared the AquaEnvironment BPV would leak down faster than the LF BPV.

Have a look at the check valve first and if the o-ring is nitrile and has failed you could try a polyurethane o-ring in the same size as they last a lot longer in that fitting. Our nitrile o-rings were lasting six months at most and now with PU they last a couple years.
 
Does not matter if the system loses pressure over a few days. It does not affect the carbon or molecular sieve. In fact, I think for the MS the opposite happens, it dries out.
 
If you have a check valve upstream and a back-pressure valve on the downstream side of the filter appliance it should not leak down to ambient pressure unless you have a leak or are leaving the system for a couple weeks with no use. I'd have a look first at the check valve by pressurizing the system then shut it down and loosen the intake fitting on your final separator. If that check valve is leaking you will detect the leak using soapy water. We can leave our systems for a month without use and it will still hold pressure albeit only to about 1000 psig.

If no leak there then likely your BPV is leaking down in the forward direction. We have had problems with this before which was solved by either rebuilding the valve or purchasing a different brand of valve. If you search the forum you'll see a thread on this I believe from a year or two ago where it appeared the AquaEnvironment BPV would leak down faster than the LF BPV.

Have a look at the check valve first and if the o-ring is nitrile and has failed you could try a polyurethane o-ring in the same size as they last a lot longer in that fitting. Our nitrile o-rings were lasting six months at most and now with PU they last a couple years.

Swamp diver.
Quite agree, great points well worth discussing.

Just would add that the OP has (from previous photos) has a Sherwood line valve at the charging filling end, so would also agree with you to first consider the filter shell inlet non return valve and that the 0-ring being the culprit. Incidentally they are Viton from memory.

However the "spring rate" may IMHO be a little high when used on these smaller <200l/min compressors and with the pulse flow effect on the spring when charging the shell to the BPR setting can incur damage to the o-ring itself as the spring seats and reseats the ball across the o-ring contact area.

Also 100% with Swamp Diver on the Aqua leak rate being greater than that of the LF BPR. Vendor choice and price I guess but that little AE unit leaks like a sieve.

Maniago and if you ever leave that Sherwood line valve open and drain down to the back pressure setting in the filter shell then by morning that AE BPR will have drained out the rest. Iain Middlebrook

---------- Post added April 13th, 2014 at 02:09 PM ----------

Does not matter if the system loses pressure over a few days.
It does.

does not affect the carbon or molecular sieve.
It will

fact, I think for the MS the opposite happens, it dries out.
It does not :)
 
errrr, Ok.....so as i see it, we've got responders on both sides of fence. I can buy both arguments - 1) any leak is sub-optimal; or 2) with small compressors and media, a leak over days just is not worth sweating over.

So let me follow-on question on #2 - if the filter tower leaks down to atmosphere, does the MS then create a "dewpoint" vacuum inside the tower such that air will try to enter the same way its escaped? Or is such that though the AE BPR does leak down, once at atmosphere, there just isn't enough of a gradient for the moisture to enter? If I lose 1 day of MS vs 30 days of pumping use because of the leak, I don't consider that an issue. Would you?
 

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Swamp diver.
Quite agree, great points well worth discussing.

Just would add that the OP has (from previous photos) has a Sherwood line valve at the charging filling end, so would also agree with you to first consider the filter shell inlet non return valve and that the 0-ring being the culprit. Incidentally they are Viton from memory.

However the "spring rate" may IMHO be a little high when used on these smaller <200l/min compressors and with the pulse flow effect on the spring when charging the shell to the BPR setting can incur damage to the o-ring itself as the spring seats and reseats the ball across the o-ring contact area.

Also 100% with Swamp Diver on the Aqua leak rate being greater than that of the LF BPR. Vendor choice and price I guess but that little AE unit leaks like a sieve.

Maniago and if you ever leave that Sherwood line valve open and drain down to the back pressure setting in the filter shell then by morning that AE BPR will have drained out the rest. Iain Middlebrook

---------- Post added April 13th, 2014 at 02:09 PM ----------

It does.

It will

It does not :)

i agree on the point about AE priorities. I made that mistake, and finally spent the extra cash and got the Lawrence factor one. Best choice. I know mani's already spent more money than he wanted but I think he'd be happy changing that priority once he sees the difference.
 
i agree on the point about AE priorities. I made that mistake, and finally spent the extra cash and got the Lawrence factor one. Best choice. I know mani's already spent more money than he wanted but I think he'd be happy changing that priority once he sees the difference.

RD are you talking about this one LAWRENCE FACTOR® &#8211; Aftermarket Compressor Parts

or this one LAWRENCE FACTOR® &#8211; Aftermarket Compressor Parts

Yeah I've spent way more than I wanted....but in for a penny, in for a pound....
 
https://www.shearwater.com/products/swift/

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