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error Miller
Error Code Fault LED
Fault LED indicator on the front panel that lights up to indicate a system fault condition.
? What Causes This
An internal system fault has been detected during operation.
✓ How to Fix It
Check the LCD display for fault condition code and message to determine the specific fault and recommended resolution.
Source: page 55 of the official manual
From the manual
This error code appears in:
Miller ProHeat 35 Industrial Heater