High Lockout
L61 on Ideal HP290

Your heat pump has detected an electrical fault within the wiring or the motor that drives the system, causing it to shut down to prevent damage.

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

Short Circuit to Compressor Terminals

What causes this fault?

This fault occurs when the electrical current flowing to the heart of the heat pump is interrupted or takes a dangerous shortcut. It is most commonly caused by damaged internal wiring or an electrical failure within the compressor motor itself, which triggers a safety shutdown. Over time, vibration or moisture can wear down the insulation on these components, leading to this electrical malfunction.

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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