BoilerFaultCodesYour boiler has detected an electrical fault with the sensor that monitors exhaust gases, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Short circuit in the flue gas temperature sensor contacts
What causes this fault?
This fault occurs when the electrical connection for the sensor that monitors exhaust temperatures becomes damaged or fails. The most common reasons are water ingress from heavy rain or moisture in the flue damaging the sensor's contacts, or the wiring harness becoming brittle and failing due to the high heat inside the boiler casing.
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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