Dometic Duo Therm AC - Only Downdraft, No Vents

[08GeorgetownBunkie]

Both of my Dometic DuoTherm AC units blow the cold air directly down from the unit instead of into the ceiling ducts. Is there a way to change this? I've tried sliding the door to close off the air from the unit, but nothing comes out of any vents. Both my air units are acting this way.


Disclaimer: This RV is new to me (2008 Georgetown)

[bikendan]

Originally Posted by 08GeorgetownBunkie

Both of my Dometic DuoTherm AC units blow the cold air directly down from the unit instead of into the ceiling ducts. Is there a way to change this? I've tried sliding the door to close off the air from the unit, but nothing comes out of any vents. Both my air units are acting this way. You can see the tab in the middle. Push it to the right to close

Is this your first RV with ducted air?


Disclaimer: This RV is new to me (2008 Georgetown)

Close the lower vent and it will route the cool air to the ceiling ducts.
It's called a dump vent and it's open.

[08GeorgetownBunkie]

"...I've tried sliding the door to close off the air from the unit, but nothing comes out of any vents. Both my air units are acting this way...."

[RVwino]

Originally Posted by 08GeorgetownBunkie

"...I've tried sliding the door to close off the air from the unit, but nothing comes out of any vents. Both my air units are acting this way...."

Remove the AC’s filter grate. You should see visible openings for the channels which lead to the ceiling vents. Possibly, the previous owner did something to block them?

[08GeorgetownBunkie]

Following up with this post. The previous owner had sealed off the ducts with aluminum tape. After removing the tape and letting it run a while, it's clear the ducts are clogged or partially collapsed (assuming they're the styrofoam type). I figure it's easiest to keep using the ACs in the downdraft mode vs. trying to investigate and unclog the ducts in the roof.

[RVwino]

Glad you figured itmout! We often turn on our bedroom AC and leave the front off. This produces cool air throughout the coach, but keeps the noise away from where we are sitting. So if you eventually decide to investigate further, something like this could help you see whether the ducts are blocked or not.
https://www.amazon.com/dp/B07MV6X4M4