BoilerFaultCodesTechnical description
Flow temperature too high
What causes this fault?
This fault occurs when the water leaving the boiler exceeds its safe temperature limit, causing the system to shut down to prevent damage. The most common reason is a lack of water flow, often caused by a failing internal pump or a blockage in the pipes that stops heat from being carried away from the burner. It can also happen if a sensor fails and incorrectly reports that the water is overheating.
This fault is more frequent during the first cold spell of autumn when heating systems are turned on after months of inactivity, which can cause internal pumps 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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