BoilerFaultCodesTechnical description
Flow temperature too high
What causes this fault?
This fault happens when the water leaving the boiler heats up too quickly or exceeds safe limits, causing the system to shut down for safety. It is usually caused by a pump failure or a blockage within the pipes that prevents hot water from circulating away from the boiler's heat exchanger. In many cases, it is the result of 'sludge' or debris building up over time and restricting the flow of water.
This fault is most common during the first cold spell of autumn when the heating is turned back on after being idle all summer, which can cause internal pump parts 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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