High Lockout
HF on Ideal HP290

Your heat pump's internal computer chips are not communicating correctly because their configuration settings do not match each other.

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 not matched to Outdoor PCB dip switch setting

What causes this fault?

This fault occurs when the heat pump’s internal control boards are sending conflicting messages about how the system should operate. It usually happens because the physical switches on the main circuit board do not match the software settings on the inverter drive, preventing the unit from starting safely. This is typically caused by a component failure or a configuration error during a recent repair.

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

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