BoilerFaultCodesIdeal C7 Fault Code
The Ideal C7 fault code means: your boiler’s internal electronic brain is having trouble communicating with the compressor pump, meaning your heating and hot water have stopped working.. It appears on 1 Ideal model in our database.
Technical description: Inverter Error
What causes the Ideal C7 fault?
This fault occurs when the main control board loses its connection with the inverter drive that powers the compressor. It is usually caused by an electrical failure within the inverter’s circuitry or a loose connection in the wiring harness that carries signals between the components. Without this communication, the system cannot safely regulate the speed of the motor, so it shuts down to prevent damage.
This fault can be more frequent during summer heatwaves or extreme winter cold, as the inverter components are sensitive to temperature extremes while working under high demand.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Ideal models that show the C7 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ideal C7 fault code information on this page is sourced and cross-checked against the official Ideal service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026