Fault codes / GE Profile AC / FC

GE Profile AC code FC

What it means: No communication with the main board: the comms (signal) wire open or shorted.

What to check

Reseat the 3-wire plug at the stat and the yellow wire at the box. Look for a pinch at the stat plate and at a slide. Also shown as two dashes.

Tech detail

12 V at the stat with FC on the screen: the yellow wire, not power.

Learn the system

• Rooftop AC
• Capacitors
• Airflow and coils
• Thermostats and AC control boards

Practice it on a service call

• AC hums and trips
• AC runs but barely cools
• AC ices up and barely blows

Guided diagnosis

• Air Conditioner
• Thermostat

Other GE Profile AC codes

• GE Profile AC code F1 Freeze sensor open or reading below -22°F
• GE Profile AC code F2 Freeze sensor shorted, or reading above 149°F
• GE Profile AC code F3 Outdoor coil sensor open (heat pump models)
• GE Profile AC code F4 Outdoor coil sensor shorted (heat pump models)
• GE Profile AC code F5 Outdoor temperature sensor open, or DIP switch 1 ON on a cool-only unit
• GE Profile AC code F6 Outdoor temperature sensor shorted (heat pump models)
• GE Profile AC code F7 The stat's own room sensor open
• GE Profile AC code F8 The stat's own room sensor shorted
• GE Profile AC code Lo 12 V under 10.5 V: the stat drops to OFF
• GE Profile AC: Snowflake flashing Indoor coil near freezing: compressor off, fan on
• GE Profile AC: Heat pump icon flashing with 32 Outdoor temperature under the heat pump lockout
• GE Profile AC: Heat pump icon flashing with 99 Indoor coil over 135°F: compressor off
• GE Profile AC: Blank display No 12 V at the stat

Full field guide: GE Profile RV air conditioner and RARWT thermostat

Codes come from the maker manuals and public service sheets. Your model's own chart always wins, and LP and 120 volt work belongs to a qualified technician.