BoilerFaultCodesYour heat pump has stopped working because of a communication or electrical issue within the internal power control system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Inverter Error
What causes this fault?
This fault occurs when the main control board loses the ability to communicate with the inverter that powers the pump's compressor. It is usually caused by a physical failure of the internal electronic circuitry or a loose wiring connection that prevents power from reaching the motor. Essentially, the 'brain' of the unit can no longer tell the motor how fast to run, so the system shuts down to prevent electrical damage.
This error is often more frequent during the first cold snap of autumn or during summer heatwaves, as extreme temperatures put the highest electrical stress on the inverter components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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