Low
LED 4 on Ideal British Gas RD

Your boiler is currently performing a routine startup check as it receives power, which is a normal part of the ignition process.

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 3

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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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