BoilerFaultCodesYour boiler is not burning gas correctly, which can be dangerous and indicates a serious combustion problem.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Indicates poor combustion. Check that flames are blue during firing.
What causes this fault?
This fault occurs when the gas and air are not mixing correctly, preventing a clean, efficient burn. The most common reasons are a build-up of dust and debris on the burner or a faulty gas valve that is providing the wrong pressure. If left unaddressed, this can lead to the production of harmful carbon monoxide.
This issue is often noticed during the first cold spell of autumn when the boiler is pushed to work harder after sitting idle over the summer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Yellow flame / excessive lifting — no call-out fees, no surprises.
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Potterton Osprey CF 125 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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