BoilerFaultCodesTechnical description
Not enough water in the system
What causes this fault?
This fault occurs when the internal sensors detect that there isn't enough water circulating through the boiler to operate safely. The most common reason is a slow leak somewhere in your radiator system or a failing component that has allowed pressure to drop below the minimum threshold. Without enough water, the boiler shuts down to prevent the heat exchanger from overheating.
This issue is frequently seen in autumn when homeowners turn their heating back on for the first time, as tiny leaks during the summer months can gradually drain the system pressure.
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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