Replacement for Ducted Dometic AC without Air Distribution Box

Updated 07/22/2026 | Published 07/17/2026

Question:

I want to replace the dometic ac unit on my 2020 Montana High Country. The unit in the living room kitchen area is ducted with no opening thru the ceiling. I want to replace it with an 18000 chill cube. What unit do I need and how do I install it. I have looked for the answers and can’t seem to find them.

asked by: Robert E

Expert Reply:

Hey Robert!

To replace the Dometic unit in your 2020 Keystone Montana High Country fifth wheel with an air conditioner like Furrion Chill Cube Variable Speed RV AC System w/ ADB & Thermostat - 18K Btu - Ducted - Black - R32 # FR49TD, you will need to create a 14-1/4"x14-1/4" opening in the ceiling. There is no Chill Cube unit that does not require an air distribution box, so that's the only way to move forward with it, and all other 18,000 BTU units that we carry require the same. I recommend contacting an installer who would be able to make that adjustment for you in order to move forward with the Furrion Chill Cube. I've linked our installer locator below for you, and you can use that to find someone in your area who we've vetted and made sure is a legitimate installer.

Where do you camp most—dry desert, humid coast, or mountain shade?

expert reply by: Jerry B