High
Boiler Overheat Thermostat on Ideal Classic FF 330

Your boiler has automatically turned off because it got too hot, acting as a safety precaution to prevent damage.

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 boiler is fitted with a safety 'cutout' thermostat. This will shut down the boiler in the event of overheating. Should this occur allow the boiler to cool, press the reset button (E) then relight.

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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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All 20 fault codes on the Classic FF 330

Seeing a different code? Every code this model can display, in one place.

5253H 1H EH FH nL 8L AL EL FLoss of system water pressureneon I 1neon I 2Neon I3Neon SGNeon SG1Neon SGINeon1Overheat thermostat lockout

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