BoilerFaultCodesTechnical description
Pressure greater than 3 bar or pump pressure increase is too high
What causes this fault?
This fault occurs when there is too much water forced into your heating system, often because the filling loop valves have been left slightly open or have developed a leak. It can also be caused by a failure in the expansion vessel, which is the internal part responsible for managing the natural pressure changes that happen when water gets hot.
This issue often surfaces when the heating is first turned on for autumn, as the heat causes the water to expand and pushes an already overfilled system past its safety limit.
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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