BoilerFaultCodesTechnical description
Heating glow return regulation
What causes this fault?
This occurs when the boiler detects that the temperature sensor on the return pipe is providing a more reliable reading than the one on the flow pipe. It physically happens because the control board senses a conflict or inconsistency in how heat is being measured as water leaves the unit, prompting it to switch its monitoring method to ensure safe operation. The most common reasons are a drifting calibration in a sensor or a slight restriction in water flow through the heat exchanger.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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