BoilerFaultCodesTechnical description
Low water pressure (below 0.5 bar)
What causes this fault?
This fault occurs when the water level inside your central heating system drops below the minimum required for the boiler to heat up safely. The most common reasons are a small leak in your pipework or radiators, or because the expansion vessel inside the boiler has lost its air charge and can no longer regulate pressure.
This code is frequently seen when homeowners turn their heating back on for the first time in autumn, as the system settles and reveals pressure losses that occurred over the summer.
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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