BoilerFaultCodesYour heat pump's internal computer system has detected a communication or electrical issue with the power supply that controls the compressor.
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 there is a breakdown in communication between the heat pump's brains and the power system that drives the compressor. It is usually caused by an electrical failure on the inverter circuit board or a loose connection in the high-voltage wiring that prevents the system from regulating power safely.
This fault is more common during summer heatwaves or extreme winter cold, as the inverter components are pushed to their thermal limits while trying to maintain indoor comfort.
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 L46 — 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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