High
S.54 on Heatline CaprizPlus 28

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.

What the manual says

Manufacturer manual

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

From this model's manual
Verified against the Heatline Capriz Plus installation & service manual, page 26.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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