BoilerFaultCodesWhat the manual says
Manufacturer manualFlow sensor damaged
Community-sourced, unverified
We could not tie this code to a specific manual. Treat it as indicative only.
What causes this fault?
This fault occurs when the boiler's internal thermometer, which monitors the temperature of the water leaving the unit, stops sending a reliable signal to the main control board. The most common reason is that the sensor has physically failed due to age or heat stress, though it can also be caused by loose or corroded electrical connections between the sensor and the boiler's computer.
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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