BoilerFaultCodesTechnical description
Primary pressure too high. Reduce CH system pressure. Check/adjust/replace primary expansion vessel 5106287
What causes this fault?
This fault occurs when the boiler's control system attempts to start the combustion process but cannot detect a stable flame. The most common reasons include a worn-out ignition spark, a blockage in the gas supply, or an internal component failing to open the gas valve correctly.
This issue is more frequent during particularly cold spells when high demand on the gas network or a frozen condensate pipe can prevent the boiler from lighting successfully.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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