Low
F on Gledhill GB35C

Your boiler has detected that the water temperature is too low and has automatically turned on its internal heater to prevent the pipes from freezing.

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

Constant - Frost protection Level 1

From this model's manual
Verified against the Gledhill Gb35c 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

Ensure the boiler's power supply remains switched onCheck that the property's main heating controls (thermostat) are turned up slightlyEnsure any radiators in cold areas are not completely turned offWait for the boiler to finish its warming cycle, at which point the 'F' code will disappear

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Related fault codes

F1View →FdView →

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