High
S.54 on Heatline Vizo 24

Your boiler has temporarily stopped heating because the water is not flowing through the system correctly, likely due to low water pressure or an airlock.

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

Waiting cycle: lack of water in the installation/temperature rise between heating fl ow and return is too high

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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