High Lockout
LB7 on Ideal HP290

Your heat pump’s internal power management system has encountered an electrical fault, causing the unit to stop running to protect itself.

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

Find a Gas Safe engineer
Search the official register →

Related guides you might find useful

Banging / kettling / whistling noise

Each noise points to a different fault.

Read →

Boiler won't turn on — 9-step checklist

Work through these before the call-out.

Read →

Boiler keeps cutting out

Lockout fault with a reset-needed pattern.

Read →