BoilerFaultCodesYour boiler is working normally but is notifying you that it has been set to provide very hot water to your radiators.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Boiler operating, high flow temperature selected.
What causes this fault?
This code appears when the temperature control dial on the front of the boiler has been turned to its maximum setting. It is not actually a fault, but rather the boiler confirming it is currently firing to reach a very high heat level for your radiators. If you find your radiators are uncomfortably hot to the touch, you can resolve this by simply turning the control knob down slightly.
This display code is more common during the winter months when homeowners turn up their thermostat or boiler controls to combat extreme cold.
DIY fix possible
Locate the temperature control knob on the boiler fascia.Turn the dial slightly anticlockwise to reduce the flow temperature.Observe if the 'H' symbol disappears or changes to a standard temperature display.
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