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

Shared across the British / Scottish 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.

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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Related fault codes

LED 4View →

All 11 fault codes on the British Gas RD

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

F2AFan start upLED 1LED 2LED 4LockoutPump overrunReverse polarityRunSensor Faults

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