High
80 on British Gas RD 430i

Your boiler has detected that the water temperature is too high, causing it to shut down to prevent damage or overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Heat output: 21.9 kW | Heat input: 22.2 kW | Gas vol. flow rate: 38.8 (l/min at tV/tR = 80/60°C)

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.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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