BoilerFaultCodesTechnical description
Insufficient system water pressure (min. 0.5 bar) resulting in the pump and fan being prevented from operating.
What causes this fault?
This fault occurs when the internal water pressure drops below the minimum level required for the boiler to fire up safely. The most common reasons are a slow leak somewhere in your radiator network or the pressure being manually drained away during recent plumbing work.
This issue often appears when you first turn the heating back on in autumn, as the expansion and contraction of pipes can highlight small leaks that developed 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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