BoilerFaultCodesYour boiler's temperature sensor is stuck on a single reading, meaning the system cannot accurately monitor how hot the water is getting.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow temperature sensor fixed value
What causes this fault?
This fault occurs when the boiler's internal computer notices that the temperature sensor is sending the exact same reading regardless of whether the burner is on or off. The most common reason is that the sensor has suffered an internal electrical failure and become 'stuck,' meaning it can no longer tell the system if the water is getting too hot. Because the boiler cannot safely monitor its own heat levels, it shuts down to prevent internal damage.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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