junction box connection

Old 03-05-03, 05:33 PM
Joe Shaw
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Lightbulb junction box connection

I am going to put a strip of electric baseboard in a second upstairs room. Can I install a junction box on the existing 220 v line that goes to another strip of baseboard and tie this second piece of baseboard to that, or should each piece of baseboard have its own line. The exsisting baseboard is a 3 foot with thermostat, the one I want to install would be 6 foot with thermostat. Thanks for any input.
Old 03-05-03, 07:25 PM
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I would think this is more in line for a different forum under electrical...not so much HVAC stuff....electricians put that stuff in..The only time we put in strip heat, we ran dedicated circuits because of the amount of power they consume. I believe they are rated in watts... (VxA), of course the feeder line to the other J box would have to be large enough to carry both loads and increase the breaker size too,...Ya see, I just think it's gonna be easier to run a dedicated branch circuit for it...I might be wrong!
Old 03-05-03, 07:57 PM
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junction box connection

Hvac01453 is correct. Dedicated circuits would be the best way to proceed. Depending on the wattage of the baseboard heater and voltage which would determine your needed wire size.
Old 03-05-03, 08:02 PM
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You should be ok with a connected wattage not to exceed 2500 watts on a 220 volt 15 amp circuit and 3500 watts on a 20 amp circuit.

I'll move this over to the electrical forum where the real experts are.
Old 03-05-03, 09:55 PM
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Start by figuring out the wattage of the existing and planned heaters, and then determine the size of the breaker controlling this circuit. It's probably okay, but you should do the math. Make sure you know for sure everything that is currently on the circuit.
Old 03-06-03, 02:05 PM
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Baseboard heaters normally equate to 250 watts per foot of baseboard length.
Old 03-06-03, 02:22 PM
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If all you have is a 3' and 6' heater, I can almost assure you that won't have a problem. Just add the wattages of the two heaters and divide by 240. The last 3' heater I wired was 750 watts, and the last 6' heater I wired was 1500 watts which are right in line with thinman's call on 250 watts per foot. 2250/240 = 9.4 amps which will do fine on a 15 or 20 amp circuit. You can use a junction box, or if it's easier, run your new line from the first heater wiring compartment.
Old 03-06-03, 06:03 PM
Joe Shaw
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Thanks alot,
My gut feeling was that as long as I don't exceed the rated amperage for that circuit I would be O.K. The idea of splicing that much power made me a little apprehensive. At this point of my project I'm not ready to hook up yet but I will definately let you know when I have.....again thanks

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