High
Overheat on Heatline Capriz 25/28

Your boiler has switched itself off because the water inside it has become too hot, usually due to a lack of circulation or a blockage.

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

Overheat LED flashing. Temperature of the water flowing from the primary heat exchanger gets too hot and the switch opens, cutting off the electrical supply to the gas valve.

From this model's manual
Verified against the Heatline Capriz 28 installation & service manual.
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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