!
error Miller
Error Code H − −
Thermistor RT1 or RT2 is open and unit is in an overheated condition. This message appears on voltmeter and ammeter displays.
? What Causes This
Unit exceeded duty cycle or thermal protection thermistors opened due to overheating.
✓ How to Fix It
- Turn off the unit and allow the cooling fan to run.
- Wait 15 minutes for the unit to cool down.
- Reduce amperage, voltage, or duty cycle before resuming welding.
- Check for blocked ventilation or airflow obstruction.
Source: page 32 of the official manual
From the manual
This error code appears in:
Miller 350P Welder