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Cannot power up T5+ Stat...
Trying to change one thermostat from a Honeywell Pro 4000 to a Honeywell Lyric T5+ but having an issue powering it up.
I have a hot water boiler for heat and air handler in basement with a condenser outside for AC - so two thermostat wires at this stat location.
I posted a diagram of how I wired it for the Lyric T5+.
Basically it's simple, for heat I connected the Red wire to R, White to W and my common wire (Green) to C. For the AC I connected the Red wire labeled RH to the RC terminal, the white wire labeled Y to the Y terminal and the Green wire labeled G to the G terminal but no luck. All the other new T5+ stats I installed are working. I did use another brand new T5+ to see if I had a bad stat but with no luck. Any help would be appreciated, thanks