Originally Posted by Eric64
It's just a little 115vt mig, worked about 2 weeks ago. Now no wire feed or power to arc. Cooling fan runs and solenoid operates just no feed or spark. after looking at the diagram looks like there is a t-stat on the secondary that may be the problem but I don't see it or recognize it. Does any of this sound like a possibility? It doesn't see that much use, just would like not to have to buy a new one if it's something that I'm just overlooking. Thanks, Eric
Eric if I remember correctly the t-stat on that welder is in the output line that is connected to the roller/feed assembly and it is located in the space between the secondary and the filter capacitor that is connected across the output connections. To check it out read across the t-stat with a volt/ohm meter on the continuity/resistance scale. You should see no resistance...in other words a direct connection across the t-stat,if it checks good then the other most likely problem is going to be the control board that is mounted across the top of the unit just above the transformer. It could be bad and not putting out the 24 volts that is required to drive the transformer.If it is bad it is not repairable and it costs 107 bucks. I have a identical unit that was given to me .I was going to use it as a wire feed for my alternator welder that I built .Come to find out the control board was bad ,so did not want to pay 107 bucks I stripped the board and the transformer out and built my own power supply/regulator with parts form Radio Shack and some junk I had .The only other thing that could be wrong is the diodes in the rectifier bridge. If everything else checks out you will need to take the diode bridge to some one who knows how to check diodes . If It were me and more than two things turn out to be bad I would just buy a new unit......but that just me.