expansion/contraction noise in ducts

[newac2]

After the blower fan starts and during the heating cycle the heating ducts crack loudly in different locations of my mobile home, Is there some specific cause of this and what can be done to limit or illiminate these sounds.

[Robert]

That is normal with the thin aluminum mobile home ducts.

All you can do is ensure skirting and underbelly is sealed up tightly and also you could insulate back of skirting.


The less that cold air gets to the ducts when heat flow is ongoing, the less the noise.



Thanks,
Robert