Dry air tanks in attic of shop?
Close
Login to Your Account
Page 1 of 3 123 LastLast
Results 1 to 20 of 51
  1. #1
    Join Date
    Jul 2008
    Location
    Milverton, Ontario, Canada
    Posts
    702
    Post Thanks / Like
    Likes (Given)
    207
    Likes (Received)
    310

    Default Dry air tanks in attic of shop?

    Since I'm going to be installing a screw compressor here shortly, Im trying to think of air reciever placement.

    Curious what the thoughts are regarding placing my air tanks in the attic of my shop?

    Air will be dry (refrigerated dryer) and filtered before hitting the tanks, but should I be concerned about moisture buildup in the tanks (from temp changes)?

    I like the idea of saving wall\floorspace in my small shop.
    I would also much prefer the safety idea of the tanks being stored out of the work envelope.

    I could run the air coming back into the shop through another dryer\filter if necessary.

    It freezes here for extended periods in the winter.

  2. #2
    Join Date
    Oct 2005
    Country
    UNITED STATES
    State/Province
    Pennsylvania
    Posts
    17,197
    Post Thanks / Like

    Default

    Just take the low point of the tank drain plug out, and replace it with a hose,
    leading down to the shop with a valve so you can easily (as in weekly) drain the tank for moisture.

  3. #3
    Join Date
    May 2019
    Country
    ALGERIA
    Posts
    16
    Post Thanks / Like
    Likes (Given)
    4
    Likes (Received)
    4

    Default

    Quote Originally Posted by digger doug View Post
    Just take the low point of the tank drain plug out, and replace it with a hose,
    leading down to the shop with a valve so you can easily (as in weekly) drain the tank for moisture.
    Unless you heat trace this line it will freeze at some point. At least in our winters this would not work.


    Sent from my iPhone using Tapatalk

  4. #4
    Join Date
    Jan 2017
    Country
    UNITED STATES
    State/Province
    Oregon
    Posts
    3,452
    Post Thanks / Like
    Likes (Given)
    712
    Likes (Received)
    2409

    Default

    I don't have any problems with water in my downstream receivers, I have one upstairs and one down on the shop floor.

    I put shutoff valves on every receiver so I can isolate the sections. Each night I close them off so I can start in the morning without waiting for the air to come up.

    So that's the only issue I would have with an attic install, more of a PITA to get to...

  5. #5
    Join Date
    Jul 2008
    Location
    Milverton, Ontario, Canada
    Posts
    702
    Post Thanks / Like
    Likes (Given)
    207
    Likes (Received)
    310

    Default

    My hope is, that by drying the air before it hits the tanks, I shouldnt have any moisture in the tanks.
    I know dewpoint plays a role in all of this.

    I just dont want to go through the process of drying before storage, and end up with moisture in the tanks anyways (and freezing up in the winter, splitting a tank).

    I suppose if need be, I could always put a heat jacket and insulation on the tanks.

  6. #6
    Join Date
    Oct 2005
    Country
    UNITED STATES
    State/Province
    Pennsylvania
    Posts
    17,197
    Post Thanks / Like

    Default

    Quote Originally Posted by overkill19 View Post
    Unless you heat trace this line it will freeze at some point. At least in our winters this would not work.


    Sent from my iPhone using Tapatalk
    Who cares where your from ?

    code says every tank must have a drain.

    If, it's a big IF, any moisture condenses in the tank, you need to drain it.

    Make it easy on yourself so it will get done.

    I'll bet some heat will leak UP, into the attic, and keep it somewhat warm.
    If you drain it, and nothing comes out, you then know you have:
    1. water
    2. it's frozen

    So then, put a heat trace on it, BIG deal.

    If your whole shop goes unheated at night, what would you doo if the tank
    was IN the shop ?

  7. #7
    Join Date
    Aug 2002
    Location
    West Unity, Ohio
    Posts
    26,002
    Post Thanks / Like
    Likes (Given)
    6293
    Likes (Received)
    8500

    Default

    Well I guess if that was a real concern, you could get by with just some heat tape on the hose where it is still in the cold confines.
    Wouldn't need to heat the whole tank.


    I Shirley don't see it splitting the tank tho.
    Plugging the drain would be about the worst that I would expect.

    ???


    ------------------

    Think Snow Eh!
    Ox

  8. Likes digger doug, DrHook liked this post
  9. #8
    Join Date
    Sep 2002
    Location
    People's Republic
    Posts
    4,374
    Post Thanks / Like
    Likes (Given)
    417
    Likes (Received)
    2664

    Default

    With a real refrigerated drier, before the tank, there will be no water in the tank

    The temp of the tank won't define moisture, more the temp/humidity of the air going into the compressor

  10. Likes tommy1010 liked this post
  11. #9
    Join Date
    Aug 2002
    Location
    West Unity, Ohio
    Posts
    26,002
    Post Thanks / Like
    Likes (Given)
    6293
    Likes (Received)
    8500

    Default

    Quote Originally Posted by gustafson View Post
    With a real refrigerated drier, before the tank, there will be no water in the tank

    The temp of the tank won't define moisture, more the temp/humidity of the air going into the compressor

    I don't know where "The Peoples Republic" is, so I have to ask:
    (China? Texas? Other?)

    Have you ever been outside on a crystal clear night at -30*C? (it doesn't need to be that cold, but...)
    Nothing but stars - maybe even so many that you can't even see constelations b/c it is so clear and there are just too many stars visible?
    The lakes froze so tight that the ice-breakers will have to werk for at least a week to get the first ore freighter through in the spring?
    (no lake effect tonight)
    So (wintery) dry that your skin wants to crack? (I have)

    .. and yet the cold temp of the night is wringing out some snowflakes?

    They didn't come from any cloud.....


    -----------------

    Think Snow Eh!
    Ox

  12. Likes digger doug, Ziggy2, DrHook liked this post
  13. #10
    Join Date
    Jun 2009
    Location
    Michigan, USA
    Posts
    2,347
    Post Thanks / Like
    Likes (Given)
    3324
    Likes (Received)
    1807

    Default

    I mounted a 50 gallon water heater tank in the rafters of my pole barn many years ago when I had a smaller compressor and wanted to have reserve of compressed air. It never was a problem and was probably there for about ten years until I bought a larger compressor and didn't need the reserve air.

  14. #11
    Join Date
    Oct 2005
    Country
    UNITED STATES
    State/Province
    Pennsylvania
    Posts
    17,197
    Post Thanks / Like

    Default

    Quote Originally Posted by gustafson View Post
    With a real refrigerated drier, before the tank, there will be no water in the tank

    The temp of the tank won't define moisture, more the temp/humidity of the air going into the compressor
    Quote Originally Posted by Ox View Post
    Have you ever been outside on a crystal clear night at -30*C? (it doesn't need to be that cold, but...)
    Nothing but stars - maybe even so many that you can't even see constelations b/c it is so clear and there are just too many stars visible? (I have)

    .. and yet the cold temp of the night is wringing out some snowflakes?

    They didn't come from any cloud.....


    -----------------

    Think Snow Eh!
    Ox
    Yup, I was going to point out that refidge dryers cool the air down to some temp.

    What is that temp ?

    If you send that air up to the tank, and it's colder, you'll drop out more condensation.

  15. #12
    Join Date
    Sep 2002
    Location
    People's Republic
    Posts
    4,374
    Post Thanks / Like
    Likes (Given)
    417
    Likes (Received)
    2664

    Default

    Quote Originally Posted by Ox View Post
    Have you ever been outside on a crystal clear night at -30*C? (it doesn't need to be that cold, but...)
    Nothing but stars - maybe even so many that you can't even see constelations b/c it is so clear and there are just too many stars visible? (I have)

    .. and yet the cold temp of the night is wringing out some snowflakes?

    They didn't come from any cloud.....


    -----------------

    Think Snow Eh!
    Ox
    I am sure this is true, and when it starts snowing in my air tank, i'll let you know

  16. #13
    Join Date
    Sep 2002
    Location
    People's Republic
    Posts
    4,374
    Post Thanks / Like
    Likes (Given)
    417
    Likes (Received)
    2664

    Default

    Quote Originally Posted by digger doug View Post
    Yup, I was going to point out that refidge dryers cool the air down to some temp.

    What is that temp ?

    If you send that air up to the tank, and it's colder, you'll drop out more condensation.
    My rubber output line frosts on mine.

    [edit]

    just went, got on my hands and knees and opened the valve, yup, 4 years exactly zero liquid water ever came out the bottom of the 400 gallon tank. Zero water out of the petcock on the shop lines, and I know no one has touched that in years

    I am not trying to say there is zero scientific amount of humidity in the air, but that once it goes through a refrigerated drier the level is so low that it won't be able to cause you a problem. My vertical tank has the drain on the bottom and the exit 3 feet up. at 10 below zero I am certain there is the possibility of a little frost, but it would never ice that line

  17. #14
    Join Date
    Sep 2002
    Location
    People's Republic
    Posts
    4,374
    Post Thanks / Like
    Likes (Given)
    417
    Likes (Received)
    2664

    Default

    Quote Originally Posted by Ox View Post
    I don't know where "The Peoples Republic" is, so I have to ask:
    (China? Texas? Other?)


    Ox
    Massachusetts, where else?

  18. Likes Pathogen liked this post
  19. #15
    Join Date
    Oct 2005
    Country
    UNITED STATES
    State/Province
    Pennsylvania
    Posts
    17,197
    Post Thanks / Like

    Default

    Quote Originally Posted by gustafson View Post
    My rubber output line frosts on mine.

    [edit]

    just went, got on my hands and knees and opened the valve, yup, 4 years exactly zero liquid water ever came out the bottom of the 400 gallon tank. Zero water out of the petcock on the shop lines, and I know no one has touched that in years

    I am not trying to say there is zero scientific amount of humidity in the air, but that once it goes through a refrigerated drier the level is so low that it won't be able to cause you a problem. My vertical tank has the drain on the bottom and the exit 3 feet up. at 10 below zero I am certain there is the possibility of a little frost, but it would never ice that line
    Theory be dammed.

    Code must be followed.

    You must have a drain.

    Period.

  20. #16
    Join Date
    Aug 2002
    Location
    West Unity, Ohio
    Posts
    26,002
    Post Thanks / Like
    Likes (Given)
    6293
    Likes (Received)
    8500

    Default

    Quote Originally Posted by digger doug View Post
    Yup, I was going to point out that refidge dryers cool the air down to some temp.

    What is that temp ?

    Sounds like you have yours set pretty low.
    Possibly wastefully low?

    I don't have much experience with dryers.
    I have one and it's hooked up to my big screw, but that unit never sees use, so ....


    -------------------

    Think Snow Eh!
    Ox

  21. #17
    Join Date
    Sep 2002
    Location
    People's Republic
    Posts
    4,374
    Post Thanks / Like
    Likes (Given)
    417
    Likes (Received)
    2664

    Default

    Quote Originally Posted by digger doug View Post
    Theory be dammed.

    Code must be followed.

    You must have a drain.

    Period.
    Who suggested otherwise?

  22. #18
    Join Date
    Sep 2007
    Location
    Northern Illinois
    Posts
    2,966
    Post Thanks / Like
    Likes (Given)
    1627
    Likes (Received)
    1789

    Default

    Quote Originally Posted by digger doug View Post
    Yup, I was going to point out that refidge dryers cool the air down to some temp.

    What is that temp ?

    If you send that air up to the tank, and it's colder, you'll drop out more condensation.
    Yup. Typically 33-34 deg. F. Any colder and you risk having the condenser freeze up. So, if you send this air up into the tank in the attic and it is zero degrees, MORE water will condense out. You may not ever find the water over the long run, however. Next summer when the tank is at 90 deg.F, the air will pick up that water and it will 'disappear'.

    There is another consideration, however, and it has a lot to do with what the air is going to be used for. We spray paint, and the last thing we need is drops of water condensing at the nozzle. The airflow expanding out of a nozzle has a cooling effect. Refrigerator dryers take this into account, and run the outgoing air through an air-to-air heat exchanger, which pre-cools the incoming air. It also heats the outgoing air well above its dew point, so even when it cools down through expansion, it remains above that dew point. If you store your air at, say, zero degrees in the attic, it will be even colder at the nozzle, and will pull droplets of water out of the surrounding air. Not good, if you are painting, or blowing dust off furniture before applying the finish. For other uses, may not be a problem at all.

    Dennis

  23. Likes digger doug, metlmunchr liked this post
  24. #19
    Join Date
    Sep 2005
    Location
    Northern California
    Posts
    860
    Post Thanks / Like
    Likes (Given)
    1
    Likes (Received)
    108

    Default

    Refrigerated air dryer will get air to a dew point of 38 degrees F or so and generally not better. IF your receiver sees temps below freezing there will be condensation. Drains are cheap and easy and smart.

    And yes I've done exactly as you suggest, a refrigerated air dryer after the "wet-receiver" and that feeds 80 gal of air storage in the rafters and another 60gal outside. Drains and drip legs cost nearly nothing to implement

  25. Likes digger doug liked this post
  26. #20
    Join Date
    Jun 2013
    Location
    Northern Il
    Posts
    1,410
    Post Thanks / Like
    Likes (Given)
    735
    Likes (Received)
    1313

    Default

    Quote Originally Posted by gustafson View Post
    I am sure this is true, and when it starts snowing in my air tank, i'll let you know
    A refrigerated drier does not take the refrigeration charge below 32F. If it did, the refrigeration coils would freeze up, eventually blocking air flow through the drier.

    The effective dew point is what is important. The efffective dewpoint also varies with pressure as does the amount of water vapor to reach saturation. The drier is only going to get you to a 32F dewpoint at best and it is usually higher, closer to 40F.

    If the receiver tank is in a heated area so that it does not go below 32F, there is usually no problem however in this case the tank will be in an unheated area so it could go below 32F. If the tank temperature goes below the dew point, then you will get condensation, especially if the tank or system pressure drops over night.

    So, a refrigerated drier will only remove so much water at a given temperature/pressure. You need to plan for the outlier conditions meaning adding a tank drain. This is also a good way to monitor the drier performance.

    When the drier is developing problems, moisture will start to show up at the drain.

  27. Likes digger doug liked this post

Tags for this Thread

Bookmarks

Posting Permissions

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