BoilerFaultCodesTechnical description
Automatictestprogramme:Returntemperaturesensor,heatingdemandsblocked.
What causes this fault?
This code appears when the boiler's internal computer notices a potential discrepancy between the flow and return temperature readings. It triggers a brief pause to double-check that the sensors are reporting accurately before allowing the burner to fire up again. Usually, this is caused by a sensor that is starting to drift out of its correct calibration or a minor circulation issue.
DIY fix possible
Wait up to 15 minutes for the automatic test to completeEnsure all radiator valves are open to allow water flowReset the boiler if the code persists for more than 20 minutes
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