BoilerFaultCodesTechnical description
Flow sensor short circuit. Check cable/connections not damaged. Renew sensor/cable. Check connections on control
What causes this fault?
This fault occurs when the electrical signal from the water flow sensor is disrupted, usually due to a physical break or a short circuit in the wiring. The most common reason is moisture ingress damaging the sensor's internal electronics or vibrating wires rubbing against internal components until the insulation wears through. When this happens, the boiler shuts down because it can no longer verify if water is safely moving through the heat exchanger.
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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