Hi all I am replacing my old round honeywell thermostat with a t8624d. The wires coming out of the wall are red white green yellow purple (blue). Unfortunately my son disconnected to old one so I have no comparison to go by. My furnace is gas with no air conditioner. Can any one help with the wiring of this unit.

Tnx

Well it seems I am in further doo doo... lol

Following the wire leads it appears that only 2 of the wires are connected at the furnace which is a janitrol gun100-4b. Out of the furnace it appears to have only 4 wires that need to be connected. They are red, white, yellow, black and blue (blue appears to be grounded to furnace). Currently the white is to the white at the thermostat and the red from the furnace is attached to the blue at the thermostat. Any Help would be appreciated.

See the sticky note on the top of the page. It explains what these wires do. Note: installers don't always use the right wire colors so you need to see where these wires go in the furnace to.