High
F- on Ideal istor HE260

Your boiler has stopped working because it has detected a specific internal problem, which it will show by alternating the 'F' with another number or letter.

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

Boiler is in lockout for a specific error. Display will be blinking, alternating with a number or letter to show which error is detected.

From this model's manual
Verified against the Ideal Isar System System 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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Boiler cover options

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