BoilerFaultCodesTechnical description
Indicates insufficient system pressure or a faulty low water pressure switch.
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below a safe level, preventing the boiler from firing up to protect the internal components. The most common reasons for this are a leak somewhere in the pipework or radiators, or simply needing to top up the system after bleeding air from your radiators.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
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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