Accessing Ducts

[rockncountry101]

I have a 2010 single wide mobile home. In my master bedroom I have ducts underneath that knock loudly and for several minutes after the heater turns off. On days that the central unit doesn't run, I never hear any noise. I know then that it has to be the ducts rubbing against something while contracting back to their "comfortable" size. My question is what would be the best way to correct this problem? The sound covers about 15 feet and even transfers the sound to a wall. It's not easy to deal with. It hasn't always done this. It was just about 4 months ago when it started. It started happening about the exact same time that a repair man was underneath fixing another unrelated problem. Could he have possibly knocked something loose? The ducts connect to the bottom of the floor joists and use 6" handlers to reach the registers. Should I just cut a 15 foot length in the underbelly and listen for the problem? Would it be easy to tape back up, or should I try another approach first? Please advise! Thanks.

[Greg]

It is hard to say how to fix the problem until you find exactly what & where the problem is. I would look first in the area that had work done.

Unless you can find a way to work through the floor openings you will have to open up the belly. If you end up opening it use a SHARP utility knife or razor blade and make a straight or an X cut. Belly tape & a hair drier is about the only way I have found to get it sealed back up, but there are methods that others have used. Do a search and you can find older posts that describe what others have done.

Greg

[UmpJJ]

It might be worth touching base with that repairman and find out exactly where he worked and exactly what he did...

UmpJJ

[rockncountry101]

They won't come back out. They told me that if I had any more issues that I had to contact the state.

[Greg]

I think I would do one better, Contact the state AND the BBB and put a complaint in.

Possibly contact an other heating contractor and get their thoughts also.

Greg