BoilerFaultCodesYour boiler is still working but cannot reach its full heat output, meaning your radiators or water may not get as hot as they should.
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.
Technical description: Boiler operating at lower flow temperature
What causes this fault?
This fault occurs when the boiler's internal controls detect that the system cannot safely reach the higher temperatures required for full power. The most common reason is a sensor that has drifted out of its correct calibration, providing the brain of the boiler with inaccurate data. It can also be caused by a faulty control board failing to send the correct signal to the burner.
This issue is often more noticeable during the first cold snap of winter when the boiler is pushed to heat the home from a cold start and fails to reach maximum output.
DIY fix possible
Check that the thermostat or temperature control knob hasn't been turned down accidentallyEnsure all radiator valves are fully openCheck for any external obstructions to the flue or ventilation
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