The T90 thermostat terminal is labeled G,F,C,H,V it is 4 wires in and jumper between G and F. The new one is a Honeywell RTH230B and has terminals marked Rh,R c,W,Y,G with a jumper between Rh and R c. Which wire do I connect to which terminal? I have a Lennox furnace and central air unit. There are 2 sets of 2 wires with 1 white and 1 black wire in each pair. G is a black wire, c is white, h is black, v is white. Jumper wire from g to f. Thanks.

the T90 thermostat terminal is labeled G,F,C,H,V it is 4 wires in and jumper between G and F. The new one is a Honeywell RTH230B and has terminals marked Rh,R c,W,Y,G with a jumper between Rh and R c. Which wire do I connect to which terminal?

I have a Lennox furnace and central air unit.

Presently T90 wire layout G and F blue, C green, H white, V red

please help with wire layout for RTH230B

Rh and Rc =
W =
Y =
G =

Did anyone get this working? I am converting this to nest

These setting worked for me but only for A/C, Nest support is sending me replacement of base board. If I swap the W with Y Heat works but in cooling mode.



T90
Nest



V
Black
RC
RH


H
yellow
W
heat


C
red
Y
cooling


F
green
G
fan


G
green
C
Common