Our trailer has Dometic A/C, Suburban furnace, and a Dometic digital thermostat. When using heat the degree offset from set temp to heat on to heat off has always been far too wide, you're roasting when it finally turns off. There's one option that reduces the temp delta but something is unhappy in the combo and it does a rapid toggle that's not right. I decided to replace said thermostat with a household digital thermostat as recommended and documented on various YouTube vids and rv threads. What a surprise to learn after removing the thermostat to find only 3 wires. Seems the Dometic thermostat is wired into a control unit inside the Dometic A/C unit that also controls the furnace. It's apparently possible to replace the control unit with a different one that includes splicing the wiring, not plug and play. Electrical is not my thing so out of luck. We'll use electric heaters when we have shore power. Maybe for the best as the furnace roars like a jet engine.