High Lockout
L31 on Ideal HP290

Your heat pump's internal control computer has detected an electrical fault with the unit that powers the motor, preventing it from running.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 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 management system fails to supply the correct electricity to the compressor motor. It is usually triggered by a short circuit or a failed component on the inverter circuit board that prevents the heat pump from physically starting its heating cycle.

This fault can be more frequent during periods of high demand in winter, as the inverter has to work harder and generate more heat to maintain high flow temperatures.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

L32View →

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