BoilerFaultCodesTechnical description
Flow temperature too high: check system flow and pump.
What causes this fault?
This fault occurs when the heat generated by the burner cannot be transferred away from the boiler fast enough, causing the internal water temperature to spike safely out of range. The most common reasons are a failing circulation pump that isn't pushing water through the pipes, or a blockage caused by a buildup of sludge and debris within the system.
This issue is most frequently seen in autumn when heating is switched back on after a summer of inactivity, 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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