BoilerFaultCodesTechnical description
Actual heat output (%)
What causes this fault?
This code appears when the boiler is placed into a manual testing mode, usually by a technician checking the system's performance. It indicates that the control board is temporarily overriding normal operation to run the burner at a fixed capacity. If you see this and no engineer is present, the testing dial on the front of the unit may have been moved or left in the wrong position.
DIY fix possible
Press the Reset button once to clear the displayEnsure the chimney sweep or service mode switch has not been accidentally activatedTurn the power off and back on at the fused spur if the code persists
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