Low
B4 on Ideal Falcon Gte

Your boiler is currently running at a low power level to maintain heat efficiently, which is a normal status indicator rather than a breakdown.

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 1st stage operating indicator from burner low fire control. Indicates low 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

Check if the heating or hot water is reaching the desired temperatureObserve the display to see if the code changes as demand increasesNo action is required as this is an operational status message

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