BoilerFaultCodesTechnical description
Low system water pressure (pressure switch)
What causes this fault?
This fault occurs when the internal sensor detects that there isn't enough water circulating in the system to operate safely. The most common reason is a gradual loss of pressure through tiny leaks or recently bled radiators, though it can also be caused by a faulty sensor or a failing expansion vessel.
This fault is frequently seen at the start of autumn when homeowners turn their heating back on for the first time after 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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