BoilerFaultCodesTechnical description
Water pressure switch fault
What causes this fault?
This fault occurs when the internal sensor detects that there isn't enough water inside the system to safely transfer heat. The most common reasons are a slow leak from a radiator valve or a loss of pressure in the expansion vessel, both of which cause the water level to drop over time.
This fault often appears when you first turn the heating back on for autumn, as the system struggles to maintain pressure after being sedentary all 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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