BoilerFaultCodesTechnical description
Temperature sensors incorrectly installed
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the flow and return pipes are heating up in the wrong order or at unexpected rates. The most common reason is that the temperature sensors have been physically clipped onto the wrong pipes during a repair, or the wiring harness has developed a fault that sends conflicting signals to the main control board.
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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