Community Forums

tomd85208 · 06-24-2014, 12:15 PM

Hi Folks, My rooftop a/c's are driveing DW and me nuts! There much too loud, especially the bedroom one. I got to thinkin about replaceing them and then I came up with an idea that might (I emphersize might) work.

Is it possible to have the front a/c unit ductwork, re-ducted to supply cool air the the rear bedroom only, and have the rear bedroom a/c re-ducted to supply cool air to the front living room & kitchen only?

Example: Turn on the front a/c when going to bed and the only noise you would hear is the whisper of air flowing out the ceiling registers and not the a/c compressor over head. Same thing goes for the front... you now turn on the bedroom a/c to cool the front of the coach and only have the rear compressor running to supply cool air to the front only.

So now the front a/c unit ONLY supplies the rear bedroom and the rear a/c unit ONLY supplies the front of the coach.

Is all of this possible? Or is it too much work for too little results?

I priced new ATWOOD A/C units a camping world and 2 new units (which are suppose to be super quiet) will set me back about $2,500.00 which is worth every penny to me if my (above) idea is unrealistic.

Any engineers out there or rv savy people that can advise me about re-routeing my a/c duct work?
Thanks in Advance!!!

Selah · 06-24-2014, 12:28 PM

I think you'll find that all the A/C are on a common duct work and not dedicate ducts to a specific A/C. To do what you are asking simple close off the supply vents in the unoccupied area. This will force the air to the other end of the coach.

texnet · 06-24-2014, 12:38 PM

Most likely the fan motors are the noise part. Replacing them is much less expensive and easy to do if you are mechanically inclined! I replace the 3 on our coach about 3 years ago and it made a world of difference. All of them had rough bearings which caused noise and vibration. Total cost was around $450 for all three fan motors.

Just a note on the ducts.. while ours has a common duct from front to back, there a baffles that partition off each A/C. Closing the vents on our coach only forces more air out the vents that are on that section of the coach.

tomd85208 · 06-24-2014, 12:42 PM

It don't work that way on my coach. The front compressor forces air only to the front of the coach. The rear a/c only to the rear of the coach. Example ... the bedroom will get super hot when only the front a/c unit is on and all the bedroom ceiling registers are fully open. No air is forced out the bdrm registers.

96 Wideglide · 06-24-2014, 04:44 PM

Hmmm, thats strange. Mine also is ducted all the way thru. Just ran the front A/C with all but the bedroom duct's closed, closed the bedroom door, and lowered the temp in there 5* in a little over an hour.

src · 06-24-2014, 05:07 PM

look at the fan i had a hornets nest on the fan put it out of balance

USMCRET · 06-24-2014, 05:21 PM

Before you do anything drastic, check the shrouds on the a/c units. They could be cracked or not secured tightly enough to prevent excess vibration. I found that to be the case on mine. A quick check is to remove the shroud, run the a/c, and see if there is a difference in the noise inside.

nutensteve · 06-24-2014, 06:43 PM

I find that with the front air running I do get some air through the rear vents in the bedroom. It seems to keep things cool enough to sleep in the evenings. I agree that the rear unit is too loud at night. I did recently replace the front air with a 15000 BTU unit.

CoCoDave · 06-25-2014, 06:47 AM

We've owned a Diplomat and a Windsor. Both had ducts that ran the full length of the coach. As others have pointed out you can run the rear unit and close the rear registers while leaving the fronts open thus forcing the cooled (or heated) air to the front and vice versa.

When taking delivery of our current coach we found the bedroom heat pump/AC was making a lot of noise. The tech who was correcting items on the punch list said that the heat pump/AC sits on a "gasket" of sorts which can get compressed to the point where you have the two hard surfaces of the heat pump/AC and roof top contacting one another. He loosened the mounting bolts slightly and the noise was dramatically reduced. The key word is "slightly" and before all the nit-pickers and worry-warts chime in, no, it does not leak.

FWIW

**TonyDi** · 06-25-2014, 07:52 AM

I'm confused. If you have ducts that run the length of the coach and are connected to separate units how do you get two zone heating/cooling? Wouldn't the temperatures in the front and rear become the same?

MSHappyCampers · 06-25-2014, 08:31 AM

Quote:

Originally Posted by TonyDi

I'm confused. If you have ducts that run the length of the coach and are connected to separate units how do you get two zone heating/cooling? Wouldn't the temperatures in the front and rear become the same?

Yeah, Tony, I know what you mean! Mine has a common duct that runs the length of the coach. My DW likes to have the A/C fan on "low" in the BR to help her sleep at night. It's pretty quiet in that mode.

JC2 · 06-25-2014, 08:48 AM

Dometic reportedly has some type of noise reduction kit that might work for you. Check this link: http://www.irv2.com/forums/f104/nois...rs-198011.html

Jeep trekker · 06-25-2014, 09:53 AM

Ours is also ducted all the way through. We run the middle air at night and close some of the registers in the front of the coach.

96 Wideglide · 06-25-2014, 10:17 AM

Quote:

Originally Posted by TonyDi

I'm confused. If you have ducts that run the length of the coach and are connected to separate units how do you get two zone heating/cooling? Wouldn't the temperatures in the front and rear become the same?

That's true, but the majority of the air comes out of the ducts closest to the unit thats running, and the thermostat for that zone is usually near by.
I'm happy mine is ducted straight thru, cause it seems the majority of the parks I stay at only have 30A, meening one AC only.