High Lockout
LC5 on Ideal HP290

Your heat pump has stopped working because of a communication or electrical fault in the main power control unit.

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 brain of the heat pump loses the ability to manage the power sent to the compressor. It is usually caused by a failure in the electrical components that convert power, or a breakdown in communication between the main control boards. Effectively, the system can no longer safely regulate the energy needed to run the outdoor unit.

This error is more frequently seen during peak summer or winter months when the heat pump is working hardest and electrical components are under the most thermal stress.

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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