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Terry Teadtke
06-11-2010, 4:47 PM
Hi folks,

I installed a new electric wall heater and thermostat yesterday and have run into a bit of a problem, I let all the smoke escape! Long story short I turned off the 20 amp breaker, hooked up the thermostat with the "black, to line" side of the thermostat to the black wire going to the breaker box and the "red,to load" wire going to the electric heater. I then connected the two white wires together in the box. Simple enough. I turned the breaker back on, turned the thermostat up to 80, and the wall heater started and warmed up real fast. I thought perfect! everything works but I've never seen a wall heater warm up so fast. Then about 15 seconds later the heater quit and smoke came out.

I went back to the breaker box and turned the breaker off. At that point I noticed the 20 amp heater breaker was the only one in the box with the white wire coming out of the breaker instead on a black wire like the rest of the breakers. It looks pretty much like all the other breakers.

I'm guessing the wall heater is toast but can't figure out what went wrong. Was the white wire going into the breaker of significance?

Thanks

Terry

Jason Roehl
06-11-2010, 6:07 PM
What voltage is the heater--120V or 240V?
What voltage is the breaker--120V or 240V?

Terry Teadtke
06-11-2010, 6:13 PM
Thanks for responding Jason

The heating unit is 120v. I'm assuming the breaker is 120v but I may very well be wrong. How can I tell if a breaker is 240v? As I said, the heater acted like it was on steroids before I let all the smoke out.

Terry

Jason Roehl
06-11-2010, 6:29 PM
If the breaker has two switches that are mechanically connected, then it's 240V (it would look like two breakers).

Okay, here's a few more questions.

Did the thermostat come with the heater?

How many wires (and what colors) come from the heater?

In your electrical panel, you said a white wire goes into the breaker. Are there other wires that exit the panel with that white wire, what are they, and where are they connected in the panel?

John Coloccia
06-11-2010, 6:37 PM
It would be very poor form for someone to use the white wire as a hot going to a panel unless it was a 220V circuit, and then the black and white would be the hots. I'm almost starting to wonder if you have a 220V circuit but the breakers aren't ganged as required. In that case, it's an absolute miracle you didn't kill yourself, and it would certainly explain why the thing blew up. One thing is clear: don't touch it until you know what you're dealing with. If it were me, the first thing I would do is kill ALL of the circuit breakers in your panel, get into the heater that you just hooked up, and measure the resistance between what you think is neutral and what you think is ground. That had better be more or less a dead short. If it's open, you almost certainly have a 220V circuit coming in, and there's another wire going to another breaker somewhere that you have to find.

Terry Teadtke
06-11-2010, 6:44 PM
Thanks again. There is only one wire coming from the breaker rather than to so that's why I was assuming it was a 120V breaker. The thermostat did not come with the heating unit. It's a Ritetemp thermostat with two red wires that say "to load" on one side and 2 black wires on the other side that say "to line". The heater is a Cadet unit. From what I could find on line instruction wise for the thermostat with 120v installations, the red and black wires L2 and T2 are simply connected together with a wire nut. I think my problem may be that I wired everything backwards since I was assuming the black wire in the power cable was connected to the breaker rather than the white wire that was in fact coming out of the breaker. meaning the thermostat was between the heating unit and ground rather than between the hot wire and heating unit but I'm only guessing.

Thanks again,

Terry

Terry Teadtke
06-11-2010, 6:49 PM
Thanks John,

I'm going to take a closer look at the breaker to see if there's a 2nd wire involved. Like I said the heating unit really heated up fast.

Terry

Terry Teadtke
06-11-2010, 7:01 PM
Oh man! I just checked the breaker box and there's 2 20 amp breakers connected to a single 12g wire cable meaning the both the white wire and the black wires were hot and the bare copper wire is used as the ground. Looks like the unit is toast. Never seen a 220 unit wired like that.

Terry

Jason Roehl
06-11-2010, 7:53 PM
For a 240V circuit, there are two things wrong then. One, and by far the most important, is that the two breakers for the 240V circuit need to be bonded together so that if one trips, they both do. Second, the white wire that is being used as a hot should have black or red tape around both ends to indicate it as a hot wire.

So, where is the black wire (coming from the 2nd circuit breaker) on the thermostat end of the circuit?

John Coloccia
06-11-2010, 8:33 PM
Oh man! I just checked the breaker box and there's 2 20 amp breakers connected to a single 12g wire cable meaning the both the white wire and the black wires were hot and the bare copper wire is used as the ground. Looks like the unit is toast. Never seen a 220 unit wired like that.

Terry

If you're a religious man, say a little thank you to your guardian angel tonight before you drift off to sleep. :D

Terry Teadtke
06-11-2010, 8:35 PM
The breakers were not connected so they couldn't both trip at once. That's another reason I had no idea both were going to the heater. I just tied the two white wires together in the box behind the thermostat. I'm going to eliminate one of the breakers and use a 110v heater as the floor has cable heat as well.

My last question is does the "line" or "load" wire on the thermostat connect to the hot wire?

I really appreciate all the help guys.

Terry

Terry Teadtke
06-11-2010, 8:36 PM
If you're a religious man, say a little thank you to your guardian angel tonight before you drift off to sleep. :D


I think I will John. I could have been an ugly situation.

Terry

Jason Roehl
06-11-2010, 9:23 PM
Here's what your final wiring setup should look like.

In the panel, there should be a black wire connected to a breaker of the appropriate size (generally, 15A for 14ga wire, 20A for 12ga, 30A for 10ga). The white wire should be connected to the neutral bus with a whole bunch of other white wires. The bare ground wire should be connected to the ground bus with a whole bunch of other bare wires. If this is your main panel, the whites and bares might be interchanged and/or have a jumper between the two buses. If this is a subpanel, the whites and bares should be electrically isolated from each other, and there should be a 4-wire feed from the main panel (two hots, a neutral and a ground).

At the thermostat then, the white wire from the panel should be connected to the white wire from the heater. If the heater has a ground, it will likely be a green wire (could be bare), so that should be connected to the bare. Then the black wire from the heater should be connected to the LOAD wire from the thermostat. The black wire from the panel is then connected to the LINE wire from the thermostat.

I'd strongly suggest at this point that you find a book on basic wiring. One with colored diagrams and photos would be most helpful.

Terry Teadtke
06-11-2010, 9:31 PM
Thanks Jason

Terry