Page 2 of 2 FirstFirst 12
Results 16 to 29 of 29

Thread: Draining condensate from air compressor

  1. #16
    Join Date
    Sep 2016
    Location
    Modesto, CA, USA
    Posts
    3,325
    A quality tank has the drain port flush to the tank bottom or a dip tube down to the bottom inside the tank.
    Bil lD

  2. #17
    Join Date
    Mar 2018
    Location
    Orwell, NY
    Posts
    241
    I bought a used small compressor/inflator machine at an auction 10 years ago or so. It has a sticker on it that says "drain tank daily to prevent water accumulation" or something to that effect. I could never find a drain on it, it had a kind of plastic cowling over all of the moving parts. Finally one day I decided to find the drain so I took the cover off and found out that it has no tank, it just goes straight from the compressor to the air hose connection. There's also no drain valve anywhere on it. I guess someone in the corporate offices must have issued an edict that all compressors were to have the "drain" sticker on them, and no one noticed that it wasn't possible on this one.
    Zach

  3. #18
    Join Date
    Nov 2016
    Location
    Richmond, VA
    Posts
    47
    Good morning! I'm setting up shop now, and I've been reading about air compressor set up and maintenance. I've read that if you leave your system under pressure all the time (which works great if you don't have leaks), there is very little water build up in the tank. I read somewhere that it's the pressure buildup that creates the condensation. If that's so, then opening up the tank to drain it promotes condensation. One post above seems to be consistent with what I read. I'd be interested in folks' thoughts.

  4. #19
    Quote Originally Posted by mark mcfarlane View Post
    For the last 2 years I have been opening up the ball valve at the bottom of my 20 gallon IR air compressor tank to drain off any accumulated water. I had been contemplating an auto drain valve that opens on every cycle, but no water ever came out. Then I realized the valve isn't at he bottom of the rounded tank, its slightly higher than the lowest point, so I titled the tank and a bunch of water came out.

    The compressor is kept in conditioned space so, even though I am in south Texas, the AC is running almost year round, and heated a few weeks in the winter,

    So what do people do to maintain/properly drain these tanks? Tilt it all the time? What is the value of an auto drain if there is still water in the bottom of the tank below the valve height.
    The auto drain isn't going to do anything that you couldn't do yourself. The tank would still need to be tilted to where the drain hole is. Is the compressor oilless? you could just prop it over to where the drain hole is all the time. If it's an oiled compressor with enough angle it might get starved for oil.

    I worked with a guy for a week onetime that at the end of every single day he let all the air out of the compressor. I finally got the nerve to ask him why he did that and he said the instructions said to drain the compressor daily. I had to tell him they meant water. I think the compressor was half full of water when he drained it that day.

  5. #20
    Join Date
    Apr 2010
    Location
    Houston, Texas area
    Posts
    1,044
    Quote Originally Posted by Edward Dyas View Post
    The auto drain isn't going to do anything that you couldn't do yourself. The tank would still need to be tilted to where the drain hole is. Is the compressor oilless? you could just prop it over to where the drain hole is all the time. If it's an oiled compressor with enough angle it might get starved for oil.
    ...
    Thanks Edward, the pump uses oil, so a permanent tilt won't work, but a great idea.

    There may or may not be a tube running down to the bottom of the tank from the water bleed valve, but I doubt it exists. This is a $600 residential compressor.
    Mark McFarlane

  6. #21
    Join Date
    Mar 2006
    Location
    SoCal
    Posts
    19,777
    Quote Originally Posted by mark mcfarlane View Post
    The drain on my IR tank is near the bottom, but on the side as seen in pic below.
    I have also had compressors with the drain a bit higher than it seems like it should be. I have never heard a good explanation of what appears to be an often repeated design flaw. Anyone know why they do this? Why not bottom-dead-center"?
    I am familiar with modern idioms but they are outside the vocabulary of what I want to say.

    - George Dyson (composer)

  7. #22
    Join Date
    Apr 2010
    Location
    Houston, Texas area
    Posts
    1,044
    Quote Originally Posted by glenn bradley View Post
    I have also had compressors with the drain a bit higher than it seems like it should be. I have never heard a good explanation of what appears to be an often repeated design flaw. Anyone know why they do this? Why not bottom-dead-center"?
    On a portable compressor, such as my IR, moving the valve a little off center provides a little bit of protection from banging it on something when wheeling around. Putting it dead center would also require making the compressor higher off the ground, raising the center of gravity a tad. Thats all I can think of.
    Mark McFarlane

  8. #23
    Join Date
    Feb 2003
    Location
    Griswold Connecticut
    Posts
    6,516
    Quote Originally Posted by mark mcfarlane View Post
    For the last 2 years I have been opening up the ball valve at the bottom of my 20 gallon IR air compressor tank to drain off any accumulated water. I had been contemplating an auto drain valve that opens on every cycle, but no water ever came out. Then I realized the valve isn't at he bottom of the rounded tank, its slightly higher than the lowest point, so I titled the tank and a bunch of water came out.

    The compressor is kept in conditioned space so, even though I am in south Texas, the AC is running almost year round, and heated a few weeks in the winter,

    So what do people do to maintain/properly drain these tanks? Tilt it all the time? What is the value of an auto drain if there is still water in the bottom of the tank below the valve height.
    Mark
    If you're going to use an auto drain, don't set it up to open after every cycle. The moisture in the tank needs to condense first and then gravity will cause it to collect in the low spot. This won't happen immediately after each compressor cycle.
    Why the drains aren't always on the bottom has been a good question. I understand all about the ideal gas laws and the effects of pressure and temperature on moisture, it would still be better to have it on the very bottom.
    Don't depressurize your tank after every use. This completely defeats the purpose of the tank. The tank is the first stage of mechanical moisture separation in a system. Yes, it also functions as a reserve volume to reduce compressor cycles, but bring the tank up to pressure every time it's used, just introduces more moisture that needs to be gotten rid of.
    "The first thing you need to know, will likely be the last thing you learn." (Unknown)

  9. #24
    Quote Originally Posted by Jay Kepley View Post
    Good morning! I'm setting up shop now, and I've been reading about air compressor set up and maintenance. I've read that if you leave your system under pressure all the time (which works great if you don't have leaks), there is very little water build up in the tank. I read somewhere that it's the pressure buildup that creates the condensation. If that's so, then opening up the tank to drain it promotes condensation. One post above seems to be consistent with what I read. I'd be interested in folks' thoughts.
    That is pure moonshine. Whoever said that, has never run a still.

  10. #25
    Join Date
    Apr 2010
    Location
    Houston, Texas area
    Posts
    1,044
    Quote Originally Posted by Mike Cutler View Post
    Mark
    If you're going to use an auto drain, don't set it up to open after every cycle. The moisture in the tank needs to condense first and then gravity will cause it to collect in the low spot. This won't happen immediately after each compressor cycle.
    Why the drains aren't always on the bottom has been a good question. I understand all about the ideal gas laws and the effects of pressure and temperature on moisture, it would still be better to have it on the very bottom.
    Don't depressurize your tank after every use. This completely defeats the purpose of the tank. The tank is the first stage of mechanical moisture separation in a system. Yes, it also functions as a reserve volume to reduce compressor cycles, but bring the tank up to pressure every time it's used, just introduces more moisture that needs to be gotten rid of.
    Mike, I misspoke. The IR auto drain has a timer you set to open the drain for 0.5 - 10 second, every 0.5 - 45 mins. It's not a full tank drain. It had been a couple years since I read the manual and forgot how it worked. I never purchased the auto drain because I wasn't getting any water out of the tank even after 1 year of service (until I tilted the tank).

    The auto drain probably is not of any value on this compressor in my environment if it takes a year to get enough water in the tank to reach the drain. I just need to manually tilt the compressor and drain once a month or something like that.
    Mark McFarlane

  11. #26
    Join Date
    Feb 2003
    Location
    Griswold Connecticut
    Posts
    6,516
    Mark

    My Rolair JC 10 has the drain at about the 5:00 position. That compressor I do depressurize when I'm done with it, and then tilt it to get any accumulated moisture out of it. I rarely use this compressor though. It could be a year or more in between uses. My 60 gallon, Rolair, upright, is a different story. It's tank always remains pressurized. After each use though, I do isolate it from the system when I am done.
    "The first thing you need to know, will likely be the last thing you learn." (Unknown)

  12. #27
    Join Date
    Feb 2003
    Location
    In the foothills of the Sandia Mountains
    Posts
    15,158
    The drain is smack dab at the bottom of my 30gal horizontal IR compressor. I added an IR ADV to it shortly after purchase. The ADV works great, I would quickly replace it if it were to die. Itís been 14 years and is still working. I later added a power switch to easily cycle the ADV. I only cycle it when Iím using air. I use a 5gal plastic can as a moisture trap. I have never needed to empty it thanks to the dry NM air.
    Attached Images Attached Images
    Please help support the Creek.

    Experience is something you don't get until just after you need it.
    - Steven Wright

  13. #28
    Join Date
    Jan 2004
    Location
    Lewiston, Idaho
    Posts
    27,141
    My Husky 26 gallon vertical air compressor has the drain at the bottom. I added the ADV and it sticks out a bit but I never move this compressor. I have a small pancake compressor I use for inflating car tires and running my nailers, etc. when portability is required.

    Unlike my friend Bruce, I leave my ADV plugged in and it cycles for 2 seconds, every 45 minutes. I do turn my compressor off when I leave the shop but the ADV remains on but that insures the tank is drained. Like Bruce, my ADV drains into a 6 gallon old paint bucket to contain the moisture in the bucket and to keep the hose from waving around when the compressor tank is charged to 140 psi when the ADC activates.
    Last edited by Ken Fitzgerald; 11-15-2019 at 9:31 PM.
    Ken

  14. #29
    Join Date
    May 2005
    Location
    Highland MI
    Posts
    3,754
    Blog Entries
    11
    I wall mounted my previous compressor and tilted it slightly to the drain end and installed a ball valve which made it much easier to drain. Also a long nipple off the bottom to act as a water sump. I since replaced it with a 60 gallon 3.7 hp Kobalt compressor which will remain on the floor, but did install a ball valve there too.

    Every time you discharge the air from your tank, it needs to be refilled with often moisture laden air. So, yes, if you drain the air every time you quit working you are likely going to end up with more water in your tank than if you don't. But if you drain the air and the water you are good to go. And folks living in humid areas will have more water issues than those in arid climates (which goes without saying, but I did anyway).
    Attached Images Attached Images
    Last edited by Ole Anderson; 11-16-2019 at 11:29 AM.
    NOW you tell me...

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •