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Honeywell RTH6500WF installation

Looking to install this unit. Says you need to have the C wire (ie. blue) in order to install. I have the wire but it was just wrapped up and pushed back into the wall so it was not used on the old thermostat. At the heater the blue wire is also just wrapped up and not used. My question is can I actual just use the blue wire on the unit and then attach the blue wire into the C port on the heater? The C port on the heater actually has two white wires already attached but they do not seem to have anything to do with the thermostat wiring.



  • SWEI
    SWEI Member Posts: 7,356
    Probably. What kind of heater is this, and what kind of controls?
  • Paul S_3
    Paul S_3 Member Posts: 1,257
    As long as its the same blue wire and no one spliced the wires in other areas.....thats what you have to find out....i would just hook it up and see what happens...is this a furnace? The other 2 white wires on the C terminal ....could be for the air conditioning and humidifier....if its not the same wire you may have to call a pro or run new wire
    ASM Mechanical Company
    Located in Staten Island NY
    Servicing all 5 boroughs of NYC.
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  • staver
    staver Member Posts: 2
    Worked perfectly Paul! Thanks alot!