Every time the heat turns off in my condominium, a loud "banging" noise is heard. So loud it wakes me up.

Question

I've had 2-different plumbers in, and they can't figure it out. I'm despirit to solve this problem. Can anybody help me with this?

Answer 1

if you have steam heat it's probably a bad trap holding water.

Call an HVAC tech.

Answer 2

Not a lot of details, so here goes...

I'm guessing you have forced air heat? If so, the cabinet is thin sheet metal and when the blower is running the sides get sucked in. WHen the heat goes off the fan slows and the sheet metal pops back out with a bang.

Fixes: It might be something as simple as a dirty air filter which creates a higher vacuum than normal - change it. If not you either get used to it, or have someone pop rivet some reinforcing angle iron into the inside or outside of the cabinet across the flexing point. (The angle pieces are at Lowes, Home Depot, etc..)