Did you use 105 Degree Celsius wire?

[83trekker]

Did you use 105 Degree Celsius wire on Mr Heater?

For the wiring on my Mr. Heater garage furance, it saids to use 105 degree celsius wiring, i have some 14/2 wire armoured i was going to use but on the wire all it sates is -40C how do you know how hot the wire can get? All of my wire has what it seems to be is the coldest it goes down too.

Also I has some wire for the thermostat but it doesnt list any sort of temp rating what so ever.

Did you all make sure to have the right temp wire for installation?

 

[Franz©]

Unless you plan to lay the wire directly across the top of the heater, I'd not be concerned. That specification is just one more case of a manufacturer covering his *** in the liability lawyer world we live in.

 

[83trekker]

Well thats exactly what i was thinking, but id imagine it must get pretty dam hot in them, all the wires have the 105 degree rating and there coating seems alot toucher then my armoured 14/2 wire. Thanks what did everybody else do, i know theres a lot of mr heater owners on here.

 

[dipper]

I plan on installing a 2 gang box up near where the heater is going to go. That'll leave enough room for an on/off switch and to have a small piece of armor cable come out of the box and loop up and into the back of the heater.

 

[porcupine73]

Hi. Yes it seems common for such equipment to want 105C wire. I think your typical NM-B and armored wire is rated for 95C; usually it is printed on the jacket for NM-B or on the tag that comes with the armored cable.

It does get hot in that area. I have the mrheater 75kbtu but I only used 75C wire...

 

[Charles (in GA)]

Use a flex conduit between the heater and a junction box on the wall and pull some THHN wire thru to the junction box. THHN is 105C wire and beyond the junction box, you can use romex or other lower rated wire.

Similarly, recessed can lights get very hot and also require 105C wire and this is what is usually done when connecting older lower temp wiring, NEC 410.67(C) gives guidance on this for lighting.

Charles