Error code
Heater overheat alarm Supplementary heater overheat
Applies to 3 models
RXC35, RXC50, RXC65
What this means
The supplementary heater's overheat protection has tripped, commonly because of poor circulation, a connector X9 problem, or a control-board fault.
When to call a technician
This fault involves refrigerant, pressure, or electrical work that must be handled by a certified technician under EU F-gas rules. Do not attempt to open the refrigerant circuit, access mains wiring, or adjust pressure components yourself. Contact a qualified installer or servicer for this one.
See the official ComfortZone manualA deep link to the manufacturer's own PDF for full technical detail. We link to manuals, we never host them.