BoilerFaultCodesTechnical description
Return sensor defective (zone 2)
What causes this fault?
This fault occurs when the boiler's control board loses communication with the temperature sensor responsible for monitoring water returning from a second heating zone. The most common reason is that the sensor has electronically failed or the electrical wiring connecting it to the main circuit board has become loose or damaged.
This fault is more common in autumn or winter when the heating is first switched on and multi-zone systems are put under constant demand.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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