Honeywell Wifi Hookup

Old 09-20-15, 06:16 AM
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Honeywell Wifi Hookup

Hi. I would like to install this wifi thermostat

Honeywell RTH6580WF Wi-Fi 7-Day Programmable Thermostat - Programmable Household Thermostats -

Here are pics of the unit. There's already a "C" wire connected, but the "C" is not run to the thermostat. I do have a blue wire that is not being used (see pics). Can I connect the unused blue wire to the "C" terminal on the thermostat as well as the "C" terminal in the unit? There would then be 2 "C" wires connected in the unit. Is this ok? Thanks.

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Old 09-20-15, 06:23 AM
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Yes, it is very common to see more than one C wire on common.

Remove power to the indoor unit before replacing the thermostat.
Connect the unused blue to C at the furnace and the new thermostat.

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