BoilerFaultCodesWhat the manual says
Manufacturer manualLow Water Pressure
What causes this fault?
This fault occurs when the internal water pressure drops below the minimum level required for the boiler to operate safely. The most common reasons are a slow leak from a radiator valve or pipework, or a loss of air pressure in the expansion vessel which helps regulate the water volume.
This fault is frequently seen in autumn when the heating is first turned on after summer, as thermal expansion can highlight existing slow leaks or pressure drops.
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 F1: no call-out fees, no surprise bills.
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