Low
-II- on British Gas RD 430i

Your boiler is currently running a routine startup sequence to fill its internal safety trap with water and is not actually faulty.

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

trap filling programme is active

From this model's manual
Verified against the British Gas Rd 430i 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.

DIY fix possible

Wait approximately 15 to 20 minutes for the sequence to finish automaticallyEnsure your thermostat is calling for heatMonitor the display until the code disappears and the boiler starts normal operation

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