Rick, I'm certainly not the most qualified person to answer heating/cooling questions, but I'll help if I can. Is the connection to your furnace a 3, 4, or 5 wire connection?
I replaced an old Honeywell Round with a new Honeywell Round CT87B. Now the fan won't come on with the heat when fan is set on auto. Any help?
I had to hire in an electrical engineer for 5 hours yesterday to trouble-shoot my solar heat collection system in conjunction with a gas fired backup which the blower was running continiously... my brother had replaced the TOP of a Honeywell CT87A base...and have 4 wires from the system. Consequently, the top piece doesn't use the green wire (Lookup Honeywell website-thermostats-ct87A! Look at page 8 of the schematics which lists which wires work on which model...) and made the gas run ANYTIME the house called for heat, even if the solar system had the heat available- resulting in a gas bill of $492 and an electrical bill of $495 last month!