I did a change out over the weekend & Someone had made a jumper ( resistor type ) on a 90 plus gas furnace ..... Anyone know the reason for the jumper ..... I think it was from w to c ......
The only problem I've had with them is if you drop one end while the other is hooked up. It will find ground...
I just got one of those magnetic jumpers that works on the new style plastic terminal strips (United Ref, $12.00) and I LOVE it. Not sure how it's gonna hold up over time, but it's saved me a lot of frustration already.