180SD Syncowave Overheat light

[DaveRedman]

I've got an older 180 Syncowave SD that I picked up at an estate sale a couple of years ago. I've made a few fun projects with it (cargo rack for the camper, ATV ramp for the truck, etc). After putting it away in September I went to use it last week and the overheat light won't turn off, and I can't get the welder to do anything at all. Any help would be appreciated.
The serial number is LA262885, Stock number is 903600 if that helps at all.
Thanks guys.

[blue_tech]

I would check for continuity with the power off to the unit. Measure through the three temperature thermostats (TP1, TP2 and TP3). You should be able to measure close to zero ohms through the three of them. Measure from RC1-5 (wire #44) to RC4-7 (wire #4) at the PC1 control board. If this is open, you need to find which thermostat is the issue, or if a wiring connection needs repaired. Once this is zero ohms through this circuit, the unit should work for you.

[DaveRedman]

Thank-you very much! :-) Now I have a point to start working repairs. Is this something a non-technical guy can work? Or should I bring it to a service center? I can work a multi-meter pretty well....are the thermostats hard wired or removable?

[blue_tech]

Dave, it depends on your comfort level with taking measurements, but the resistance measurement I discussed can be taken with all power off to the machine, so it is a fairly safe thing to check. It may develop to taking measurements with the power on and this is usually something that should be done by someone with electrical training. The thermostats are mounted within the unit, but can be replaced if you really find a defective one. You may just find a loose connection within those thermostats and you may not need to replace anything, but just fix the loose connection.

That all being said, you are welcome to take my suggestion to your local welder repair shop if you don't feel comfortable with repairing your item.