I know that I’m resurrecting an old post, but thought that I would provide the info in case someone was searching for it in the future.
I just finished replacing two ducted Coleman Mach 15s in my Solitude (one with heat pump, the other without) with the ductless Chill Cubes.
In the 14x14 opening I blocked off the duct openings using foam blocks then covered with aluminum tape. The airflow on the ductless chill cubes is “backwards” so you can’t use the ductwork to distribute cool air even if you wanted to since the ducts would act as unfiltered returns back to the unit.
The Ductless Chill Cube does not include any provision to run a furnace. But since I had the Coleman Mach unit I was able to leave the 12V+, 12V-, and (white) furnace connection in the 14x14 opening in place so the existing thermostat can continue to be used to run the furnace. I just disconnected the unused cooling wires from the Coleman control box and taped them off.
I am familiar with the Air Command and you will not be able to do the same since it’s a communicating device and requires the control board in the AC unit to maintain comms. My suggestion is to use a battery-powered residential thermostat for the furnace, something like a Honeywell TH1100DV1000 or any other battery-powered “millivolt compatible” residential thermostat would work. Or if you want something RV-specific an Easy Touch 352 is compatible.
Your other still-functional ducted unit would continue to provide air to whatever vent openings it supplies now.
By the way, the reviews talking about the reduced noise are mostly accurate. When running on low fan speed the Chill Cube is insanely quiet and it moves a decent amount of air. We have small portable fan in the bedroom and with the AC fan on low it’s no louder than the portable fan. Once you increase the Chill Cube’s fan speed it gets louder. Medium is still quieter than the Coleman, but High is equal to the Coleman on low and Turbo is louder than the Coleman on high.
