[username123]

Hello,

I tried wiring a 240v baseboard heater using a double-pole breaker and single pole thermostat. I connected both white and black at the breaker, paid attention to line/load using the black at the thermostat, wire nutted the white, and connected at the heater per instructions. When I flipped the breaker there was a large arc and one of the pole of the breaker is toast. What did I do??

[tkrussell]

The way you describe the circuit sounds fine, if so there must a dead short in the cable, or a wire rubbed up against sharp metal, something like that to cause a short like that.

Just to be sure, and you probably did this already, but trace out the wiring. Can you sketch it out and post it here? You can use Paint and save as a jpg file to get it here the easiest.

[username123]

Hello,

I tried wiring a 240v baseboard heater using a double-pole breaker and single pole thermostat. I connected both white and black at the breaker, paid attention to line/load using the black at the thermostat, wire nutted the white, and connected at the heater per instructions. When I flipped the breaker there was a large arc and one of the pole of the breaker is toast. What did I do???

Thanks for the reply tkrussell. I got everything working today. The only thing I can come up with is that a wire nut shifted as I was jamming everything into the box. I looked the whole thing over, re-nutted everyhing good & tight, then put it back together on a new breaker. I've got heat! One of the heaters is humming, though. I'm going to read the old threads for an answer to that. If you have any thoughts, I'd love to know. It's pretty annoying.

Thanks Again