Baseboard Heater Voltage

[A-1Sparky]

I've got a situation where the customer ordered 208V rated heaters and they have 240v available for them. Will the higher voltage burn up the elements prematurely? I've run 240v to 208/240v baseboards before, but never to straight-rated 208v. Thanks.

 

[iwire]

If they are not rated 240 there is no way I would connect them to 240.

They would run much hotter and could be potential source of fire or injury.

 

[augie47]

Can't answer your element life question, but installing it on 240 would be a violation of 110.4.

 

[A-1Sparky]

Thanks guys. That's what I figured, but wanted to make sure.

 

[LarryFine]

Heating equipment that is rated for 240v but run on 208v operates at 3/4 of the rated power. The reciprocal of 3/4 is 4/3, or 1-1/3, which is how much of the rated power a 208v heater run on 240v will operate at.

Unless the manufacturer merely re-rates 240v heaters, doing what you asked will no doubt burn the heaters up. Only the manufacturer can tell you whether you can safely operate the 208v-rated heaters at 240v.

 

[Howard Burger]

Larry, how do you get 3/4? The 208:240 ratio is .87. Is 1.73 involved somehow? Thanks

 

[LarryFine]

Larry, how do you get 3/4? The 208:240 ratio is .87. Is 1.73 involved somehow? Thanks

You're talking voltage, I'm talking wattage. Calculate again. (Hint: 0.87 x 0.87)

 

[Howard Burger]

Oh, yeah. P=E(sq)/R. Thanks

 

[George B.]

Heater calculations

Heater calculations

First I would try to get in touch with the manufacturer to be safe. If you have the book FERMS FAST FINDER there is an interesting electric heat calculations section in there that may be worth investigating. I have the 2005 book and page 46 has some information and formulas. Be Safe