BoilerFaultCodesTechnical description
CH flow sensor fault: CH flow sensor (8000 - 20000 ohms at room temperature), Wiring and connections to sensor.
What causes this fault?
This fault occurs when the boiler's internal sensors continue to detect a flame or electrical current even after the gas valve has been closed. The most common cause is a carbon-clogged sensing electrode sending a false signal, but it can also be triggered by a fault in the main control board or a short in the internal wiring. Because it is a safety concern for the boiler to 'see' fire when it shouldn't, the system shuts down completely to prevent damage.
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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