BoilerFaultCodesTechnical description
Water pressure switch error – contact not closed
What causes this fault?
This fault occurs when the boiler detects that there isn't enough water pressure inside the system to operate safely. The most common reason is a slow leak somewhere in your radiators or pipework, but it can also happen if the expansion vessel has lost its air charge and can no longer regulate pressure correctly.
This issue often appears when you first turn the heating back on in autumn, as small leaks or air pockets that developed over summer become apparent once the system is under load.
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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