High
Lockout lamp on Warmworld FFC 30/60

Your boiler has switched itself off because it has become too hot or there isn't enough water moving 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.

What the manual says

Manufacturer manual

The flue thermostat has tripped due to exceeding a pre-set temperature or the overheat thermostat has tripped due to insufficient water flow rate.

From this model's manual
Verified against the Warmworld Ffc 30 60 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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Related fault codes

OverheatView →Flue OverheatView →

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