Troubleshooting guide
Coleman-Mach thermostat shows GAS or flashing Elec assist
Use this when a Coleman-Mach thermostat indicates backup gas heat is assisting or electric heat is temporarily locked out after repeated unmet heat calls.
Use this atlas to identify likely meaning and prepare for service. Shut off power, LP gas, fuel, or water when a listed appliance condition involves flame, gas smell, exhaust, generator shutdown, high temperature, moving jacks/slides, refrigerant, 120 VAC, control boards, repeated ignition failure, or a persistent lockout. Call the appliance maker, RV dealer, or a qualified RV technician for repair.
Owner-safe checklist
- Treat GAS or flashing Elec as backup heat behavior described by the thermostat manual.
- Record outdoor temperature, heat mode, zone, and how long the heat call has been running.
- Wait through the manual-described lockout period if the coach remains safe and warm enough.
- Do not change upper control-board settings or heat wiring.
Code tables for these appliances
- Coleman-Mach RV thermostats 14 codes