I installed an Aprilaire whole house humidifier and the drain from it is going into the floor condensate pump that my AC also drains into. The outside portion of drainage hose from the condensate pump is about 10ft long and goes into a downspout. This worked fine until we got very cold overnight temperatures in CT. I woke up to the condensate pump running continuously and a pool of water on the basement floor, because the outside portion of the drain hose had frozen up.

I would like to reroute this condensate pump drain line inside to prevent this from happening, as the humidifier will need to run all winter. I have a sump pit with a plastic radon sump cover that is close by, or the septic waste line PVC pipe that is tied into old cast iron pipe going out to the septic tank. What is the best way to do this, and how would I tie into the existing? Thank you.

1 Answer 1


I would dump it into the sump pit. If you do that, you may be able to do away with the separate condensate pump as, depending on the relative elevation between condensate pit and the sump pit, gravity should carry the water from humidifier down to the sump pit.

I would not tie it into the sewer drain that goes out to the septic tank. I don't know about the code relative to septic systems, but in most jurisdictions with public sewer it is against regulations to dump things like sump pump outflows or humidifier excess water into the sewer system. This is a form of infiltration, and is bad for the waste water treatment plant (WWTP).

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