I am replacing an old round thermostat with a new one. The old one had red wire to R and Rh terminals, white to W, yellow to Y and green to G. What thermostat do I need to replace this one. It controls both heat and A/C

Any heat/cool thermostat will work. They all come with detailed instructions and even little stickers to keep track of the wiring.

All thermostats like this are wired the same using the same terminals.