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Need advice installing cold room dehumidifier condensate line

RandomNJGuy2021 | Posted in General Discussion on May 27, 2021 10:13pm

Hello.  Newbie here, hoping for some advice.  I have a cold room underneath my front porch adjacent to a finished basement.  During the summer, it gets quite humid which limits how we can use the room.  

I’d like to install a dehumidifier in there with a pump to automatically drain the condensate.  This would only run in the summer, humidity where we’re at is fine during the other seasons.  Two things I’m trying to figure out:

1) What’s the best way to route the condensate line through the block masonry wall of the cold room.  I’m leaning towards taking the 1/4 tube condensate line from the dehumidifier and using a 1/4 barbed adapter to tap into a 1/2″ PVC line. Then I would run this 1/2 PVC through a 1″ hole made by a 1″ masonry bit.  Does this make sense or should i step up to 3/4″ pvc?  

2) What I should do with the condensate once it’s outside the cold room.  It seems i have two good options.  The first is to tap into a nearby gutter downspout that attaches to the exterior wall of the cold room.  The second is to tap into a nearby exterior clean out for my basement’s gravity drain system.  I’m leaning towards the gutter downspout because it seems simpler, but what’s the best way to tap a gutter downspout with a condensate line?

Any thoughts/suggestions/feedback are appreciated.  Thanks in advance.

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Replies

  1. User avater
    unclemike42 | May 29, 2021 07:36am | #1

    I think it is good practice (might be code) to have a condensate line end with a gap from wherever it drains. (to avoid back-flow)

    You could install a downspout Y and route PVC to end where it drains into the downspout.

    I would want to make sure it runs downhill all the way to avoid freezing issues.

    1. RandomNJGuy2021 | May 29, 2021 04:21pm | #3

      Thank you. What's the best way to create that air gap between the PVC line and the downspout Y?

  2. catmandeux | May 29, 2021 01:46pm | #2

    How much condensate will the dehumidifier be producing?
    I think the 1/2 PVC should be sufficient for a dehumidifier. Check the specifications for the pump capacity and head.

    What is outside the cold room?
    If a garden bed, feeding the water into a drip tube will help keep the plants happy.

    1. RandomNJGuy2021 | May 29, 2021 04:25pm | #4

      It's a 50 pint dehumidifier, so in a worse case scenario I think we're talking about 6 gallons per day or so. On the other side of the coldroom wall is a narrow bed containing boxwood hedges.

  3. User avater
    unclemike42 | May 29, 2021 07:05pm | #5

    Also, know that sooner or later condensate lines get filled with gunk and have to be cleaned out.

  4. User avater
    tfarwell | Jun 01, 2021 11:26am | #6

    I have condensate lines for my heat pump and two water heaters. There's not that much water - I just let it run out of the ground. No issues for the part 15 years. I use a 3/8" line on my heat pump (it has a condensate pump), and I use 1/2" PVC for the heat pump water heaters (gravity)

    To run the line through the block, I'd use a piece of PVC as a sleeve, and run the plastic line through it. If you need to replace it - they can get clogged - it's easier.

    Best of luck.

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