I have a White-Rodgers 1F56W-444 ac/heat thermostat. I want to replace it with a Honeywell RTH110B thermostat.

When I remove the old thermostat, the wires are connected from the wall to the thermostat as follows:

R -> Rc
G -> G
W -> W
B -> Y
Y -> A

What is "A"? The new thermostat does not have an "A". It has Rc, Rh, W, Y, G.

If the yellow connects to the Rh, do I need to remove the jumper between Rc and Rh?

Help?

Thanks.

Taking the faceplate off the wall, I see the yellow wire is connected to the back of the faceplate. Do I need this wire for the new thermostat?

FIXED!
Connected the wires as noted in the original question. The yellow seems to be related to the old thermostat.

At first, nothing happened... then I remembered the power was shut off at the breaker box. Then nothing happened again. But there is a security delay built into the startup, so after a few minutes, the ac came on. Thank goodness... it was 85 degrees in the house.