Annoying duct noise when heat is on/off

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Jmaclicious
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Joined: Mon Oct 17, 2016 6:18 pm

Annoying duct noise when heat is on/off

Post by Jmaclicious » Sun Nov 25, 2018 8:37 pm

I had all my ductwork, furnace and ac replaced about 2 years ago... and every winter when the heat is on/off it knocks/pops every so often, and even more frequently when the heat turns off for the first few minutes... at night time its severely annoying. Is this a result of me framing a short wall tight underneath the duct work, or the fact i have no insulation in the basement? .... summer time i dont have this problem with the AC. What can I do in order to get this solved so i can actually sleep at night instead of listening to this noise.


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A. Spruce
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Re: Annoying duct noise when heat is on/off

Post by A. Spruce » Sun Nov 25, 2018 11:33 pm

Your ducts are going to make more noise with heat than they do with cold. If you framed tightly against metal duct, that is probably the source of the problem. The metal expands when it warms up and shrinks when it cools off, this creates movement, movement creates squeaks and thunks when that metal is touching framing.

If the noise wasn't there before you built the walls/enclosed the ducting, then you definitely created the problem with the framing. If it was always there and worse now, well, the ducting is rubbing in other places then too.
If the women don't find you handsome, they should at least find you handy.

plott hound
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Re: Annoying duct noise when heat is on/off

Post by plott hound » Mon Nov 26, 2018 11:22 am

Find the noisey spot then cross check or crease the the duct with a screw driver.

Jmaclicious
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Joined: Mon Oct 17, 2016 6:18 pm

Re: Annoying duct noise when heat is on/off

Post by Jmaclicious » Mon Nov 26, 2018 3:01 pm

A. Spruce wrote:
Sun Nov 25, 2018 11:33 pm
Your ducts are going to make more noise with heat than they do with cold. If you framed tightly against metal duct, that is probably the source of the problem. The metal expands when it warms up and shrinks when it cools off, this creates movement, movement creates squeaks and thunks when that metal is touching framing.

If the noise wasn't there before you built the walls/enclosed the ducting, then you definitely created the problem with the framing. If it was always there and worse now, well, the ducting is rubbing in other places then too.
I just cut 3/4" off the studs and brought the top plate down to get off the duct work, Ill see how it is tonight if that makes a difference. :) Thanks for that suggestion Spruce!

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