High Lockout
LBC on Ideal HP290

Your heat pump's internal motor controller has encountered an electrical problem and has stopped working to protect the system.

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 inverter, which acts as the 'brain' controlling the speed of the pump's motor, detects an electrical irregularity or a direct hardware failure. The most common reason is a malfunction within the internal circuit board or the compressor itself, which causes the system to shut down to prevent further electrical damage.

This fault can be more prevalent during extreme summer or winter temperatures when the compressor is under the highest operational load and the inverter components are prone to overheating.

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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