BoilerFaultCodes.com
7x High Lockout

Your boiler has detected that the water temperature in your central heating pipes is getting too hot or is not flowing correctly.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: problem exists with the flow temperature (2nd CH)

What causes this fault?

This fault occurs when the boiler's internal sensors detect that the water is heating up too quickly or reaching dangerous temperatures without being moved away. The most common reasons are a pump that has stopped circulating water or a blockage in the system, causing the heat to build up inside the unit rather than being sent to your radiators.

This issue is more frequent in autumn when heating systems are switched back on after being idle all summer, which can cause internal pump parts to seize.

Typical repair cost £90-180 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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