I'm planning to install a low voltage driveway snow melt system that will require 70A (240V). I want to run this from a new 100A subpanel in my attached garage. My problem is that my 200A service is split into two 100A main panels. How would I accomplish this? My other option I suppose is to run a new 100A service from the meter, but I would rather not as the disconnect box at the meter is full with two 100A breakers (one for each main panel), and it seems this would require a new meter box (expensive).

TIA,
Doug

stanfortyman

I don't get it. How much was this snow melt system? I bet that was expensive too, huh?
Why is it always NO problem dropping a chunk of money on something cool, like a hot tub or driveway snow melt system, yet it is always too expensive to have the proper electrical work done to have it installed safely????

Do you realize how much this system is going to cost to run????? After a couple of storms you'll forget how much the electrical work was.



To answer your question, NO, you cannot likely hook this system into either panel. 70A will most likely overload either one. Unless you can move some circuits to one panel to lighten the load, but then you run the risk of overloading that panel.

How big is this house?
How old is it?
What large electrical loads are there?
Where is it located?

Washington1

DWD,
you need to do a demand load calculation. This will help tell you if what you are installing will work.

If your furnace, range, and hot water heater are electric, then I would say you are pushing it. Yet, a DLC is best.

stanfortyman

DWD, you wasted your own time, you did not answer my valid questions.

Yes, the first part of my reply was criticism, but the second half is trying to help.
Sorry if you are to thin skinned for a little justified criticism.

Answer my questions and we can try again.