Low
5.0 on British Gas RD 430i

Your boiler is currently running at its maximum capacity to bring your home up to the desired temperature and is not actually reporting a fault.

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

Max. heating output

Shared across the RD 430i 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

Check if your thermostat is set to a very high temperatureWait for the house to warm up to see if the code clears naturallyMonitor the boiler to ensure it eventually scales back its power output

Find a Gas Safe engineer
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Boiler cover options

Avoid the next call-out bill

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Related fault codes

1.0View →2.0View →3.0View →4.0View →

All 32 fault codes on the RD 430i

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

-II-0.02.02.42.52.77.030405060708090100A1b1C1C4C6d3E2E9EAF7FAFCFdP1P2P3

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