BoilerFaultCodesTechnical description
High fume temperature – the exchanger probe detects an excessive temperature
What causes this fault?
This fault occurs when the internal sensors detect that the gases leaving your boiler are significantly hotter than they should be, triggering an automatic shutdown to prevent damage. The most common reason is a buildup of limescale or debris inside the heat exchanger which prevents heat from being transferred to your water, or a faulty sensor giving an incorrect reading.
This issue is more frequent in winter when the boiler is running at maximum capacity for long periods, causing internal temperatures to peak.
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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