BoilerFaultCodesTechnical description
Water pressure is too low
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below the minimum level required for the boiler to fire up. The most common reasons are a slow leak from a radiator valve or pipework, or the air pressure in the expansion vessel has depleted over time, causing water to be expelled through the safety valve.
This issue is more frequent in autumn when the heating is turned on for the first time after summer, as the change in temperature can highlight minor leaks or air pockets.
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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