Terminal confusion. T90 general control thermostat replacement with new one.

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 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? Thanks Tom M.

I installed a new honeywell RTH7600D thermostat and connected the Red wire to the Rc terminal instead of the are terminal and left the jumper in as the manual suggested. Is it possible that it shorted out the transformer in the Furnace? Because even thuogh I have correctly now connected the Red...

Hello: I saw your name on an internet search for thermostat wiring problems, so I thought I would try you for this one. I could not get help elsewhere. I have an oil burner, and a separate a/c unit. I installed a programmable thermostat 2 years ago that works well, although the location is...

Hi! My furnace's control board recently blew and the repair guy replaced it with a different kind. Aparently the new board requires a wire from the thermostat to the G terminal to work the A/C fan, and the old one didn't. The repair guy would need to make another trip for this repair. I am...