Troubleshooting guide
Coleman-Mach thermostat fan only or no cooling call
Coleman-Mach thermostat manuals separate Fan Only or manual fan behavior from cooling calls; if FAN operates but COOL mode, zone, and setpoint do not request compressor operation, the issue may be mode/zone setup or service-only HVAC controls.
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
- Confirm COOL mode, selected zone, fan Auto/On setting, and setpoint below room temperature from the thermostat display.
- Wait through any built-in compressor delay before deciding the cooling call failed.
- Record thermostat model, display text, zone, and whether Fan Only was selected.
- Call qualified RV HVAC service if the thermostat requests cooling but the compressor never starts.
Code tables for these appliances
- Coleman-Mach RV thermostats 14 codes
Official sources
Coleman-MachColeman-Mach 9330-33 Multiple Zone Thermostat Controller SystemColeman-MachColeman-Mach Digital Thermostats 9420-381 & 9420-382Coleman-MachAirxcel 9430 Series Wall Thermostat Installation and Operation InstructionsColeman-MachColeman-Mach 6535-335 2 Stage Heat Pump Wall Thermostat Installation and Operating InstructionsColeman-MachColeman-Mach 6536-335 2 Stage Heat Pump Wall Thermostat Installation and Operating InstructionsColeman-MachColeman-Mach Frequently Asked Questions