BoilerFaultCodesTechnical description
Temperature is too high during central heating demand.
What causes this fault?
This fault occurs when water cannot flow through the boiler quickly enough to carry heat away, causing the internal temperature to reach a dangerous level. The most common reasons are a failed pump that isn't pushing water around or a physical blockage, such as air or sludge, trapped within the main heat exchanger.
This fault often appears during the first cold spell of autumn when the heating is turned back on after a long summer break, which can cause internal pump components to seize.
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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