Lincoln Electric LN-25 PRO DUAL POWER Service Manual page 57

F-7
Observe Safety Guidelines detailed in the beginning of this manual.
PROBLEMS
(SYMPTOMS)
No shielding gas.
No Display, Machine operates
correctly otherwise.
No or incorrect amperage reading
on the display.
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely,
contact the Lincoln Electric Service Department for technical troubleshooting assistance before you proceed.
Call 1-888-935-3877.
TROUBLESHOOTING AND REPAIR
POSSIBLE AREAS OF
MISADJUSTMENT(S)
GAS SHIELDING ISSUES
1. The gas supply is off or empty.
2. The gas hose is cut or crushed.
3. The flow meter is closed. Dirt or
debris is in the solenoid.
4. There is a loose connection at
the solenoid.
5. The solenoid has failed.
1. Loose connection on the Preset
(Display) PCB or the Control
PCB.
2. Damaged Preset (Display) PCB
or Control PCB.
1. Loose connection on the Preset
(Display) PCB or on the Current
Transducer.
2. Damaged Preset PCB.
3. Damaged Current Transducer.
CAUTION
LN-25™ PRO DUAL POWER
RECOMMENDED
COURSE OF ACTION
1. Verify the gas supply is ON and
flowing.
2. Reroute the gas hose to avoid
sharp corners and make sure
nothing is on it. Repair or
replace damaged hoses.
3. Open the flow meter valve.
4. Apply 80 psi of filtered air to the
solenoid to remove dirt and
debris.
5. Remove the cover and verify
that all the connections are in
good condition.
6. Perform the Gas Solenoid
Test, replace if necessary.
1. Check J1 on the Control PCB
and J8 on the Preset PCB for
a good connection.
2. Perform the Preset (Display)
PCB Test.
1. Check J10 on the Preset
(Display) PCB and J11 on the
Current Transducer for a good
connection.
2. Perform Preset (Display) PCB
Test.
F-7