My existing Honeywell thermostat is connected to the furnace/AC via 4 wires, but the cable itself is a 5 wire cable. The blue wire is just unused in this current configuration. How should I connect my new 2441TH thermostat to the furnace using the 5 wires? I have attached a picture of the furnace/AC wiring. Thank you for any assistance.
furnace.jpg
furnace.jpg
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