Automatic Compressor Purge Valve - Silencer or Not?

[HoosierBuddy]

Hey guys,

I bought one of these:

https://www.amazon.com/gp/product/B01IT9FD1E/?tag=atomicindus08-20

Automatic purge valves to put on my air compressor as I am absolutely terrible about remembering to purge it by hand. That one is the only one I could find that allows you to set a very long delay between purge cycles (up to 99 hours). I set mine to purge once per day for 30 seconds.

So...as you might guess...it's really loud.

Curious if I could use one of those sintered bronze fittings "pneumatic mufflers" to cut the noise down. My worry is would I still get enough flow to get all the water out?

Thanks for any advice you might have!

Phil

 

[sberry]

How often are you using this. 30 seconds is a lot. 10 per day if it's used some is plenty.

 

[rlitman]

I have my (manual) purge valve plumbed into the bottom of a 2-gallon pretzel "barrel" filled with gutter stuff foam. It cuts all the noise out, and captures all the water.

A purge cycle for me takes 2 seconds max, and I purge it once a day when I'm using it, and not at all on days I'm not in the shop. An ideal purge valve would be able to hear the noise and shut off. When it's purging water, it is quiet. Once it gets loud, it is merely wasting air.

 

[HoosierBuddy]

Good info guys. I'll cut that purge time down to 10 seconds or maybe less.

I think for $10 I'll go ahead and get one of the mufflers and just install it and then wait a couple of weeks and take it out and see if an unusual amount of water is expelled. If so...that will tell me not to put it back in.

Phil

 

[rlitman]

Good info guys. I'll cut that purge time down to 10 seconds or maybe less.

I think for $10 I'll go ahead and get one of the mufflers and just install it and then wait a couple of weeks and take it out and see if an unusual amount of water is expelled. If so...that will tell me not to put it back in.

Phil

Now that I think about it, I wouldn't use a sintered muffler for this. It's way too much like a filter that will clog up. They're meant to capture the clean exhaust from a tool, not your tank drain.

Something like this would be better:
https://www.amazon.com/dp/B000CZ2Z74/?tag=atomicindus08-20

 

[HoosierBuddy]

Now that I think about it, I wouldn't use a sintered muffler for this. It's way too much like a filter that will clog up. They're meant to capture the clean exhaust from a tool, not your tank drain.

Something like this would be better:
https://www.amazon.com/dp/B000CZ2Z74/?tag=atomicindus08-20

I don't see a pressure rating on that.

I'm running my tank about 130 psi.

I share your concern on the sintered product, but a few online reviewers on Amazon were using it for exactly this purpose. We'll see. If I hate it, I'll toss it and maybe fabricate something similar to what you show above.

Phil

 

[ebruce]

Set your timer to purge in the middle of the night, assuming it's in a detached garage. Then you won't notice or care how loud it is.

 

[rlitman]

I don't see a pressure rating on that...

There is no pressure rating on a muffler, because it's "open" on both ends. The pressure across it should always be negligible, unless it's clogged up.

My concern with the sintered product is that if you're not around to hear it blow that one time per day, you may never realize that it's clogged, so it may stop draining over time.

One option would be to put in a tee, with the sintered muffler on one outlet, and a pressure relief valve at the other. Something that blows at say 50PSI. Then cover the relief valve outlet in paper or something that will indicate that it has blown.

 

[pgilmore7]

I just installed one of these on my compressor, I agree it’s loud. I think I’m just going to run the line outside so it won’t be so loud in the shop.

 

[fitter30]

Just throttle the valve down to a acceptable noise.

 

[Milton Shaw]

If it is 1/2 pipe thread use just a Briggs and Stratton muffler. They work, won't clog up and really do quieten down the air noise. I put one on the exhaust from my single post lift and it makes a tremendous difference. Just a few dollar unless you have an old mower around.

 

[rlitman]

If it is 1/2 pipe thread use just a Briggs and Stratton muffler. They work, won't clog up and really do quieten down the air noise. I put one on the exhaust from my single post lift and it makes a tremendous difference. Just a few dollar unless you have an old mower around.

I like that idea. Better than (though very similar to) the bubbler.

 

[HoosierBuddy]

OK...I'll try the muffler idea too. Will compare and contrast and report back.

BTW...if anyone else gets the same valve let me warn you to not do what I did. I let the air out of the tank via a blow down valve on my outlet piping, removed the needle valve I'd been purging through and installed this valve in its place. After the second or third cycle it would not shut off.

I took the valve off, removed the solenoid and disassembled the valve down to its component pieces. Underneath the diaphragm I found the valve passages chock full of wet brown stuff....rust that my old needle valve wouldn't pass. I cleaned it all out, reassembled the valve THEN ran my tank up to about 80 PSI and blew it down through the purge piping to empty ALL the junk out of it. Since then the automatic valve has worked fine.

In hindsight it is obvious that I should have blew it down through the purge line as step one of the whole project.

Phil

 

[LS6 Tommy]

Install a good strainer upstream, pipe in a manual bypass and clean everything regularly. I've never seen any electric auto purge valve that didn't plug up, even ones with strainers.

Tommy

 

[Stuart in MN]

Those little sintered metal silencers do work, a purge cycle is still not quiet but it will be a lot better than what it sounds like without one.

 

[HoosierBuddy]

Install a good strainer upstream, pipe in a manual bypass and clean everything regularly. I've never seen any electric auto purge valve that didn't plug up, even ones with strainers.

Tommy

Great idea Tommy. I will do that for sure.

Phil

 

[gerryw]

Heres my set up; 1/2 copper to candy jar filled with sponge , hole in bottom to let it drain.
No longer scares the **** out of me or my wife ( compressor in basement.)
Gerry

 

[sberry]

3 vessels, piped to a common tube thru the wall. If I run the snot out of it give them a crack, if its been a while I do it when I read a bunged up auto drain thread. Found enough used copper water tubing I only needed to make 1 flare.