On 12 Nov 2005 16:08:36 -0800, "charlesg"
wrote:

For those who read the other post, I dropped the recessed wall heaters
idea.

I am planning an addition where I would indstall two plain 4 ft.
electric baseboard heaters controlled by their own thermostat (one
thermostat for both). The rest of the house has hot water radiators. I
figured I would by two 750W 3' units from QMark or Comet (the room is a
little over 100 sq. ft.)

First, I am wondering what the big difference is between 120V vs. 240V
(beside the obvious). What would make me pick one over the other?

I am also having a hard time figuring out the wiring. On the wall, I
should have one wire going to the unit #1 and one wire down to the
basement. Do I need a relay box of some kind down there? I was also
gonna put both units on one breaker, daisy chained together if you
will. Is that a bad plan?

Since we're contracting the work out ourselves, I am trying to be as
prepared as possible when the electrician comes by to quote me on the
work.

Thanks.
If you use a line voltage thermostat (common for this situation) you
would just run the feed from the panel into the junction box of the
heater, and two wires from the thermostat there as well, and make the
proper connections in the junction box.

If you use a low voltage thermostat you will need a control
transformer and a relay.

Most baseboard units have a chase so you can run extra wires along the
unit to daisy chain them together.

Are you sure you will need 1500 watts to heat 100 square feet? Sounds
like a lot...guess it won't hurt though, will just cycle faster if you
have more watts than you need.

If you go with 240 units the current will be half (doh!). For your
application it won't make much difference since one 12 ga circuit will
be enough for the two heaters. Half the current will be a little
easier on the thermostat if you go the line voltage tstat route. 240
is a tad more efficient since you get less voltage drop in the wire
due to half current...but unless you've got a really long run it won't
be much.

HTH,

Paul