BoilerFaultCodesYour heat pump has stopped working because the internal computer that controls the speed of the motor 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 power electronics responsible for regulating the compressor's motor detect an electrical abnormality, such as a sudden voltage spike or a loss of communication between components. It is often caused by the internal control board failing due to heat stress or an electrical short within the compressor itself.
This issue can be more prevalent during summer heatwaves or periods of extreme cold when the inverter is working at maximum capacity to maintain indoor comfort, leading to increased thermal stress on the electronics.
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 L6E — 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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