Miller Electric 350, 350P Troubleshooting, Temperatures are within acceptable limits see -2and

.A complete Parts List is available at www.MillerWelds.com

6-6. Troubleshooting

Trouble	Remedy
No weld output; wire does not feed.	Be sure line disconnect switch is On (see Section 3-15or 3-16).
	Replace building line fuse or reset circuit breaker if open (see Section 3-15or 3-16).
	Secure gun trigger connections (see Section 3-7).
	Have Factory Authorized Service Agent check Power switch.
	Have Factory Authorized Service Agent check all board connections and main control board.
No weld output; wire feeds.	Thermistor RT1 or RT2 open (overheating). Allow fan to run; the unit will be enabled when it has cooled
	and temperatures are within acceptable limits (see Section 3-2and 6-2).
	Connect work clamp to get good metal to metal contact.
	Replace contact tip (see gun Owner’s Manual).
	Have Factory Authorized Service Agent check main control board and main rectifier.
Low weld output.	Connect unit to proper input voltage or check for low line voltage (see Section 3-15or 3-16).
	Have Factory Authorized Service Agent check main control board and user interface board.
Low, high, or erratic wire speed.	Readjust front panel settings (see Section 4-1).
	Change to correct size drive rolls (see Section 6-4).
	Readjust drive roll pressure (see Section 3-17).
	Replace inlet guide, contact tip, and/or liner if necessary (see gun Owner’s Manual).
	Have Factory Authorized Service Agent check input voltage.
	Have Factory Authorized Service Agent check main control board.
No wire feed.	Turn Wire Speed control to higher setting (see Section 4-1).
	Clear obstruction in gun contact tip or liner (see gun Owner’s Manual).
	Readjust drive roll pressure (see Section 3-17).
	Change to correct size drive rolls (see Section 6-4).
	Rethread welding wire (see Section 3-17).
	Check gun trigger and leads. Repair or replace gun if necessary.
	Have Factory Authorized Service Agent check main control board and user interface board.
	H − − message appears on voltmeter and ammeter displays to indicate thermistor RT1 or RT2 is open
	and unit is in an overheated condition (see Section 6-5).

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