Noisy rooftop ac

Dirt dauber nests will cause an imbalance and louder

MFL wrote:
OP does not give any info, age, brand of AC, trailer make, but not much sound proofing to be done.

Since the OP hasn't provided any information about A/C make / model nor trailer make / model that also raises the question as to whether this is a direct blow A/C or a ducted system. Having owned both I'd suggest that a ducted system is inherently going to be somewhat quieter in operation than a direct blow and because direct blow are most often found in smaller trailers it's not surprising one would assess a direct blow as being noisier as you're never that far away from it. My current Dometic Brisk II is direct blow and there's no question it's noisier than the ducted system I had in our previous KZ Spree.

Our Coleman Mach 15 (15000 BTU) has two settings: Extremely Loud and Even Louder Yet.

Now, if something is out of balance, like a load of dirt or a nest in outdoor fan or indoor blower wheel, it can add noise you can reduce with a cleaning.

Also, if the sealed system is rubbing on part of the A/C, that'll add noise to the mix. Our first Coleman was a Mach 3 (13500 BTU). It was noisy and I found a problem with the rubber cookies the compressor rests on. Too long to remember exactly what was wrong, but basically it was going metal to metal when it should have been riding on rubber. And I was able to get it back in its proper position and back onto rubber. I also found some of the wiring was rubbing on the compressor and the insulation was about to go through. So all in all the noise was a GODsend.

Terryallan wrote:
Make sure it is not loose.

OP does not give any info, age, brand of AC, trailer make, but not much sound proofing to be done. Check to see that mounting bolts are snug, but not tight.

Doug, I think OP means that trailer is lightly constructed, causing more noise from the AC.

Jerry

tibba wrote:
Has anyone sounproofed their rooftop a.c.? Mine is really loud, probably due to measures taken to keep trailer light.

They're ALL loud. :E I've owned a variety - Carrier AirV, Dometic Brisk Air, Coleman Mach 3+, and currently a Dometic Brisk II which claims that "Fan motor sound dampening brackets reduce noise and vibration" . Yeah, right - it also claims a maximum fan rate of 350 cfm which in turn means that inside the camper it sounds much like a jet engine. "Quieter" my foot :M ... ear shattering noise is the nature of the beast and you just have to live with it if you want to be cool. :p

Roof AC units are just that. They make NO models that are lighter and will be louder. Post the Year/Brand/Model of the AC unit. Doug

Moved from Forum Technical Support

Make sure it is not loose.