BoilerFaultCodesYour boiler has stopped working because it cannot correctly measure the temperature of the water leaving the unit.
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 (NTC) interrupted/short-circuited
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the temperature of the water heading to your taps or radiators. It is usually caused by the sensor's internal electrical components failing over time or the connecting wires becoming loose or damaged. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E2 — no call-out fees, no surprises.
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