Low
B5 on Ideal Falcon Gte

Your boiler is working at its higher power setting to meet a heavy demand for heating or hot water, and everything is functioning as it should.

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

Feed to 2nd stage operating indicator from burner high fire control to boiler panel. Indicates high fire in operation.

From this model's manual
Verified against the Ideal Falcon Gte 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

No action is required as this is an operational status message rather than a fault.Monitor the boiler to ensure it returns to standard operation once the demand for heat reduces.

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