BoilerFaultCodesWhat the manual says
Manufacturer manualWater Switch System pressure too low | Water Switch - plug disconnected Waterswitch activated
What causes this fault?
This fault occurs when the boiler's internal safety sensor detects that there isn't enough water pressure flowing through the heat exchanger to operate safely. The most common reason is a gradual leak in the central heating system or air trapped in the pipes, but it can also be caused by a loose wire or a faulty pressure switch failing to send a signal to the main control board.
This fault often appears after the summer break when the heating is first turned back on, as static water pressure can drop during long periods of inactivity.
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.
Avoid the next call-out bill
A cover plan would handle faults like F.25: no call-out fees, no surprise bills.
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