High Lockout
9.1.31 on Ideal HP290

Your heat pump has stopped because the refrigerant gas is getting too hot, likely due to a blockage or restricted water flow through 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

Condensing Temperature High Error

What causes this fault?

This fault occurs when the refrigerant gas inside the unit reaches a dangerously high temperature, causing the system to shut down for safety. The most common reason is that heat isn't being moved away from the unit fast enough, often due to a blockage in the pipes, a failing pump, or a build-up of sludge in the system filter.

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

9.1.28View →9.1.30View →

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