BoilerFaultCodesYour heat pump has stopped working because the internal power control system has detected an electrical fault.
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 brain of the heat pump loses communication with the power system or detects an electrical surge. It typically signals that the inverter board has failed or is trying to protect the compressor from damage due to unstable voltage. The system shuts down immediately to prevent expensive electrical components from burning out.
This fault can be more frequent during summer heatwaves or extreme winter cold when the inverter is under maximum load to maintain target temperatures.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like L47 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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