Said It Here

Can I drain my dehumidifier into an unknown basement pipe?

Connecting a dehumidifier to an unknown basement pipe requires figuring out what the line was intended for and whether you need a trap or air gap. DIY installation attempts can lead to mistakes like using too much glue that blocks water flow, leaving the unit running without any visible drainage.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    Draining into the water softener
  2. 2
    Running the line into a floor sump pump
  3. 3
    Testing the pipe capacity with a continuous run or inspecting it with a sewer camera
  4. 4
    Hiring a professional to do the installation

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.

r/hvacadvice1 person · September 2026

Im not the best at diy but trying to learn. Ran to Lowe’s bought a threaded 3/4 elbow. Connected to a 3/4 p trap. Then a connector to a threaded area to receive the hose adapter.source ↗

cavvz · r/hvacadvice · 1 upvotes

Unit has been on for almost an hour and I’m not seeing water flow. Is there a world where I maybe used too much glue and it’s blocking water ?source ↗

cavvz · r/hvacadvice · 1 upvotes
r/Plumbing1 person · September 2026

I was wondering if I could drain/pump my dehumidifier into it (the white 1/4” line in the photo).source ↗

Is it obvious what this pipe/circle in front of it would’ve been intended for? Can I pump my dehumidifier into it (if so, do I need a trap, air gap, something else)?source ↗

joshgroves · r/Plumbing

Where this came up

People with this problem also raised