wrote in message ...

More likely there will be a pile of disasembled parts
all over the place. He seems to prefer that to focusing
on the obvious. So, the furnace doesn't fire up. Who
starts by taking apart the tstat, asking 100 questions about
how to debug it, without going to look at the furnace and
seeing that the blower door is off, that he took off a few
months ago? Good grief.

I have to give him credit for the longest threads, the most
pics, etc. IMO, he should just call a tech.

He definitely needs to slow down a bit and wait for a few more
TSR tips to show up.

Trouble shooting starts with the basics, not what one suspects
unless the symptoms are a known, recurring event. By setting
up the system for a normal start sequence, and waiting the
appropriate amount of time, all of the issues with the T-stat
would not have been.

If the system was reset and things were started over again I
would wager that the unit would work again. This time, do
the test with the cover in place. Check for normal operation,
first, then find out why things are not working. Find the path
of electricity (hence, the logic of the circuit), and follow
it until the path stops. Just bumping the interlock would not
cause any of the other safeties to engage, and would restart
the start up sequence.

Just as with physics, observation with repeatable results is
necessary to figure out what is going wrong. As for his AC, I
wonder if there is a blown fuse out in the fusible disconnect
outside.