2nd air conditioner on 297RST

jcairns57 · 01-30-2018, 03:58 PM

I ordered a Dometic a/c unit to install over the bedroom on my 2015 297RST but could not install it because the distance from the wall separating the bathroom & bedroom was too close. The air distribution/control box won't fit on the ceiling because it is too large. There is only 5.75 inches from the cutout to the wall. Anyone have ideas of which a/c manufacturer makes a smaller unit that will fit?

Thanks

SeaDog · 01-31-2018, 07:32 AM

Why not center the new AC over the bed? It would require you cutting to fit

jcairns57 · 01-31-2018, 09:10 AM

The hole is already factory cut & has an existing vent & is prewired for a/c.

SeaDog · 01-31-2018, 09:17 AM

You best bet may be to contact the factory and ask what unit they install in that position, unless it was designed for a fan only installation.

jcairns57 · 01-31-2018, 09:21 AM

I already contacted them. The service rep said she couldn’t recommend anyone’s a/c unit. Thanks

NMWildcat · 01-31-2018, 10:29 AM

I believe there is usually a size difference on the ceiling assembly air distribution panel between ducted and non-ducted. We used a low profile Penguin II ducted and the inside portion is fairly small. Might check out the dimensions on their webpage. Good luck!

jcairns57 · 01-31-2018, 11:29 AM

Ya. The one I need will be non-ducted. Great. Thanks

NMWildcat · 01-31-2018, 11:36 AM

Quote:

Originally Posted by jcairns57

Ya. The one I need will be non-ducted. Great. Thanks

Just curious as to why non-ducted? In my limited experience (installed second a/c on two different units) the units that were pre-wired also had access to the duct system. Just had to remove blocker plate and/or insulation.

jcairns57 · 01-31-2018, 11:42 AM

I’ll have to check. I didn’t see a blocker plate in there when I took the vent out. I’ll double check tho. Thanks

NMWildcat · 01-31-2018, 11:46 AM

I have read that in some units, the 'duct' is just a gap in the hard foam insulation. Might check if your existing vents are attached to an actual duct or not.

jcairns57 · 01-31-2018, 12:11 PM

Support from Forest River just returned my call. It’s gotta be a non-ducted unit.

AquaMan · 01-31-2018, 12:15 PM

Quote:

Originally Posted by NMWildcat

I have read that in some units, the 'duct' is just a gap in the hard foam insulation. Might check if your existing vents are attached to an actual duct or not.

I would say that in most units, the duct is just a channel in the ceiling and the the vents are only connected to the ceiling material itself. If you look at the vents, they are usually in a fairly straight line front to back. See what side of the hole the vents are on and knock out that block to access the channel. If you want to double check before knocking the block out, drill a hole in it, plug a few vents, and turn your existing ac fan on. You should feel the air.

NMWildcat · 01-31-2018, 12:26 PM

Quote:

Originally Posted by jcairns57

Support from Forest River just returned my call. It’s gotta be a non-ducted unit.

Well dangit. It was worth a shot

rracer5 · 01-31-2018, 12:45 PM

Quote:

Originally Posted by AquaMan

I would say that in most units, the duct is just a channel in the ceiling and the the vents are only connected to the ceiling material itself. If you look at the vents, they are usually in a fairly straight line front to back. See what side of the hole the vents are on and knock out that block to access the channel. If you want to double check before knocking the block out, drill a hole in it, plug a few vents, and turn your existing ac fan on. You should feel the air.

This is true however, there needs to be a "return air" duct running from side to side. Two return air vents then have to be cut into the ceiling just inside the 2 outer sidewalls at the ends of the return duct. To do this type of install correctly probably would require pulling ceiling panels down to install the return duct system & tie into the existing cold air outlet duct system.

NMWildcat · 01-31-2018, 01:06 PM

Quote:

Originally Posted by rracer5

This is true however, there needs to be a "return air" duct running from side to side. Two return air vents then have to be cut into the ceiling just inside the 2 outer sidewalls at the ends of the return duct. To do this type of install correctly probably would require pulling ceiling panels down to install the return duct system & tie into the existing cold air outlet duct system.

Return air routed through 14" x 14" hole a/c and ceiling attachment (air distributor) is mounted to.

jcairns57 · 01-31-2018, 01:20 PM

Thanks guys. Found a solution. [emoji106]

NMWildcat · 01-31-2018, 01:38 PM

Quote:

Originally Posted by jcairns57

Thanks guys. Found a solution. [emoji106]

Share solution please!

AquaMan · 01-31-2018, 01:40 PM

Quote:

Originally Posted by NMWildcat

Return air routed through 14" x 14" hole a/c and ceiling attachment (air distributor) is mounted to.

I concur!

jcairns57 · 01-31-2018, 03:43 PM

Coleman Mach 3 with series 9000 ceiling air diverter/controller. Small enough to fit between wall & roof cutout.

Casey r · 01-31-2018, 04:52 PM

Quote:

Originally Posted by NMWildcat

Just curious as to why non-ducted? In my limited experience (installed second a/c on two different units) the units that were pre-wired also had access to the duct system. Just had to remove blocker plate and/or insulation.

Scott
What did you do about a thermostat. I have not looked at the duct work but I did pull out the vent and I have 110 volts there no other wiring. I assumed since I did not see thermostat wiring it was not ducted. I did see thin pylwood on the side that would be closest to the ducting but did not remove it. Wanting to add second a/c.

You may also like: