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Heating & Air Conditioning Plumbing DIY

Condensate drain from furnace, noise from drain stack...

4 years ago

last modified: 4 years ago

Hello -

We live on the top floor of our building above two other units and recently (seems to correspond with renovation of bottom floor in our stack of units) we've been hearing acoustic noises originate from a drain stack located on the floor of our furnace room. The noises happen at set times during the day and in rhythmic waves, initially it sounds like water cascading/flushing and then it abruptly stops with a tap/bump....wait 5 seconds....and the cycles starts again. It happens for about 15-20 minutes at the same time every morning, almost when someone might be showering to get ready for work. Anyway...

The drain where the acoustic noises originate receives what appears to be the condensate from our furnace through a PVC pipe that is routed from the furnace to the drain. The top of the drain is open to the air and the smaller condensate PVC pipe isn't secured in any way (see photos), so it just kind of disappears into the larger drain and there is some play/movement.

I realize the real solution is to address this problem at the source, which we are researching with our homeowners association, but in the meantime I'm curious what our options are for dampening the noise. Can we cover the top of the drain with sound insulation or does it need to be open/exposed in order to breathe or vent? What insulation would one recommend? There isn't much clearance against the baseboard, so wonder what our options are. Any other thoughts or ideas?

Appreciate any help or insights!

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Comments (2)

PRO
Austin Air Companie
4 years ago
That condensate pipe is for your AC, not your furnace.

I doubt you are running your AC right now, it's cold most places right now.

Because you have a gas furnace it's unlikely your AC is a heat pump. So the noise you are hearing is probably more related to plumbing than HVAC system.

The thumping and tapping may be coming from water heater. If it is cold where you are and you haven't been running the AC I would get a plumber to investigate your water heater and plumbing system.

There looks to be a water shut off valve toward the top of the picture you posted. What does that go to?

It could be water hammer noise from the condo being renovated. Maybe they subbed out plumbing to a general contractor and he made a mistake?
Stax
4 years ago
lol
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