BoilerFaultCodesYour boiler is struggling to burn gas correctly and efficiently, which can lead to it locking out to ensure safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Adjust CO2. Set the CO2 content.
What causes this fault?
This fault occurs when the boiler's sensors detect an incorrect mixture of gas and air during the combustion process, meaning the flame is not burning as it should. The most common reasons are a drifting gas valve that needs recalibration or worn-out spark electrodes that are struggling to ignite the gas cleanly. In some cases, it can be caused by a fault in the main control board failing to manage the gas flow accurately.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like S.62 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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