BoilerFaultCodesYour heat pump's internal control system has detected an electrical communication error or a fault with the motor drive board.
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 heat pump's internal brain loses communication with the power unit that drives the compressor. It is usually caused by a physical failure of the inverter circuit board or loose electrical connections between the main control components. Effectively, the system can no longer send the correct signals to start the heating process, leading to a complete shutdown.
This fault can be more prevalent during summer heatwaves or extreme winter cold, as the inverter board is sensitive to temperature extremes while under heavy electrical load.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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