Low
LED 3 on Ideal British Gas RD

Your boiler is currently undergoing a routine internal startup sequence as it receives power, and this light pattern simply confirms it is initializing its control system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Application of power. Flash > 1/sec in sync with LED 4

From this model's manual
Verified against the Ideal British Gas Rd installation & service manual, page 35.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait for the boiler to complete its startup process, which usually takes a few seconds.If the boiler remains in this state for more than a few minutes without starting, turn it off at the fused spur switch for 30 seconds.Turn the power back on to force a fresh restart.

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