Rob wrote:

On Wed, 29 Nov 2006 13:49:21 -0600, Chris Friesen
wrote:

Hmm. I wired it up exactly as you described. Thermostat powers up
normally and runs through self test. I set the temperature, and I
heard it "click" and the display shows it's turning the heater on,
however, the heater never comes on. Any idea on what I could be doing
wrong?

Hmm...I'm thinking I misunderstood the old one. I forgot it had only
two wires. I'm sorry, I gave you bad advice.

You should probably rewire the old one back in before continuing--the
two blacks hooked to the two red leads get nutted together with the old
red lead, and the other black gets nutted with the remaining black wire.

The two black wires that were nutted together with the red before should
stay nutted together. These are likely one leg of the supply (but we
can't be 100% certain without checking).

The black wire that was nutted to the black thermostat wire before is
likely one leg of the wall heater, but again, we can't be 100% certain
without checking.

The white wires may supply the other leg of the circuit to the wall
heater, although ideally if they're hot they should be taped to identify
them as such.

If you have a voltmeter, check the voltage between the black wires (that
were nutted with the red before) and the white wires. If this is 240V
then you know that the black wires are one side of your supply, and the
white is the other.

If this is the case, then you can nut the black inner lead to the two
black wires, and the black outer lead to the remaining black wire. Then
nut the inner red to the three white wires and see if that works.

If you can identify that one of the three white wires goes to the
heater, then you could pull it out and nut it to the outer red lead,
leaving the inner red lead nutted to the remaining two white wires.

Chris