BoilerFaultCodesYour boiler is struggling to accurately measure the water temperature in a specific part of your heating system, which may cause your heating to run inefficiently or not at all.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: With flow temperature sensor for low loss header (automatic adjustment upon recognition)
What causes this fault?
This fault occurs when the boiler loses communication with the temperature sensor located on the low loss header, which is a component that balances water flow in larger or complex heating systems. The most common reason is a faulty sensor that has failed electrically or a loose connection in the wiring that prevents the boiler from monitoring the system's true temperature.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 52:1 — no call-out fees, no surprises.
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