High
L 0C on Ideal Independent System2 S15

Your boiler is repeatedly attempts to start up and failing, causing it to lock itself out for safety after five unsuccessful tries.

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

Restart occurs 5 times within 15 minutes

From this model's manual
Verified against the Ideal Independent System2 S15 installation & service manual, page 48.
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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