BoilerFaultCodesYour heat pump’s internal power control system has encountered an electrical fault, preventing the unit from heating your home.
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 internal electronics that manage the power sent to the compressor fail or detect an electrical surge. It is usually caused by a component failure on the control board or the compressor itself becoming electrically unstable, meaning the system can no longer safely regulate the motor's speed. Because the heat pump cannot vary its power output, the entire system shuts down to prevent further electrical damage.
This fault can be more frequent during periods of extreme external temperatures when the compressor is required to run at its highest power capacity for long durations.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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