BoilerFaultCodesYour heat pump’s internal power management system has encountered an electrical fault, causing the unit to stop running to protect itself.
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 power converter, which controls the speed of the compressor, detects an electrical irregularity or an internal component failure. The most common reason is a malfunction within the inverter's circuitry or a communication break between the brain of the unit and the motor control system.
This fault can be more frequent during summer heatwaves or periods of extreme cold, as the inverter is forced to work harder to maintain target temperatures, putting more stress on the electrical components.
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 LB7 — 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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