BoilerFaultCodesTechnical description
Primary system water pressure too low (< 0.5 bar).
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below a safe level, causing the boiler to shut down to prevent internal damage. The most common reasons are a slow leak from a radiator valve or pipework, or air being released from the system through the radiators or an internal auto-air vent.
This issue often appears when you turn your heating back on after summer, as the change in temperature can reveal small leaks or trapped air in the pipes.
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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