BoilerFaultCodesYour boiler's internal temperature sensor is failing to provide a correct reading, preventing the heating from starting up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Central heating (CH) flow negative thermistor coefficient (NTC) sensor defective
What causes this fault?
This fault occurs when the sensor responsible for monitoring the heat of the water leaving your boiler fails to send a consistent signal back to the main control board. The most common reason is the electrical component inside the sensor has worn out or corroded, meaning the boiler can no longer monitor safety temperatures and must shut down. In some cases, it can also be triggered by a loose electrical connection or moisture damage to the wiring leading to the sensor.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like E2 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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