Hi,

I have recently purchased a Honeywell wireless thermostat
(YTH6320R1015). Manual is here, page 4 is key:
http://www.pexuniverse.com/docs/pdf/...-guide-efs.pdf


I have split setup: A gas boiler in the basement (2-conductor thermostat
wire). My relatively modern Bryant AC unit is in the attic. I therefore
have two transformers. (For what it's worth, I've made sure they have
the same phase.)

I would like to control both systems with my thermostat. Honeywell tech
reps all agree that this must be possible, but give me contradictory
instructions. After several exchanges they seem to come to an agreement
that I might need a third transformer just to power the unit
independently from the transformers in my systems.

Does that make sense or could there be an easier solution!

Many many thanks in advance!

Sam