The short answer
An RV thermostat has to match your air conditioner's control system, not just its brand. Two Dometic thermostats can look alike and not work with the same unit, and the same goes for Coleman-Mach. Before you order, you need to know three things:
Your AC's model number (rooftop unit and ceiling assembly). See how to find your RV AC model number.
What the thermostat controls: cool
…