"Robert11" wrote:

I guess what's confusing me is the "2 stage thermostat" part.

A thermostat which has controls for the additional heater stage. This
requires additional wires in the bundle, so unless they replace the
existing wires, something else has to be done.

By 2 stage on the stat, do they, perhaps, just mean a programmable setback
temp., or is it really that you need this type to control (properly) a 2
stage furnace such as the Trane gas, forced hot air furnace I will be
getting installed shortly.

I paid extra to get a good tstat to go with my new Lennox last fall,
with the new wire pull and all. Temp stayed right on the money all
winter.