
Originally Posted by
Albemarle
The system is a gas furnace. I have an A/C unit outside which connects into the furnance and then blows cool air throughout the house. The Honeywell manual says not to use the RH and RC jumper for 2 or 5 wire installations. Please advise if you still recommend removing the orange wire from the RC slot and then placing the jumper in the slot connecting to the RH slot.
Thank you.
I read the Honeywell manual.
You did not tell me where the wires were placed on the old thermostat so I have no idea what orange is actually used for.
The color code is not always followed and without the knowledge of where the wires were connected to the old thermostat makes being accurate impossible.
I need to know what the orange wire was connected to on the old thermostat or you will need to track down the orange wire and see where it lands on the equipment.
The main difference is weather or not your system is using two transformers or if it is a standard system that uses only one transformer. So if the outside A/C unit has its own transformer then you would have a two transformer system. In that case you would use another wire to power the cooling side of the thermostat. I have no idea if the orange wire you have is for that purpose or not since once again you did not tell me where the orange wire was landed on the original thermostat.
Below you will see in the file that the orange wire is usually used in a heat pump system for the reversing valve.