New thermostat for gas furnace.

Discussion in 'HVAC' started by connsu, Dec 15, 2018.

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  1. Dec 15, 2018 #1

    connsu

    connsu

    connsu

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    We want to add another thermostat for the downstairs of the house. We have one for the upstairs already. We think we know the wire that goes to the thermostat but won't know until we cut it. It just looks like a brown wire now. How hard is it to add another thermostat to the furnace?
    Thanks in advance!
     
  2. Dec 18, 2018 #2

    pjones

    pjones

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    Inside that brown wire is anywhere from 2 to 10 other wires.

    Power needs to be turned off when you cut that wire or you will blow the transformer.

    Programmable thermostats need to be programmed and setup to communicate properly with your furnace or it could cause damage to your equipment or improper operation.

    If you feel comfortable with that then you should be ok. If it makes you squeamish then it might be best to hire someone to do the job. It typically takes about 2 hours after travel is factored in, for most programmable thermostats, if you have someone else install it for you.
     
  3. Dec 18, 2018 #3

    EdInKentucky

    EdInKentucky

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    everything pjones said,
    hire someone to install the new thermostat,
    I can tell from your post, that you're not skilled enough to do it.
    Get help.
     
  4. Dec 18, 2018 #4

    kok328

    kok328

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    I'm reading this as the OP wants to have two thermostats attached to one furnace.
     
  5. Dec 19, 2018 #5

    pjones

    pjones

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    Oh, I see what you mean... you might be right about that.

    In that case it won't work. You will be forever fighting it and trying to figure out which thermostat is in control and what one you have to adjust to change the temperature because they won't communicate between each other.

    You will want to get a thermostat that can accept a remote sensor to either average the two temperatures that you are measuring (thermostat and remote sensor temps) or use it to control the temperature from the remote location.

    Almost any pro series digital Honeywell thermostat should be able to do this and let you select if you want to use the remote temp as an averaging sensor or a controlling sensor.

    I've had great feedback from the T6 series thermostats but I personally prefer the Pro8000 series (or above) touch screen thermostats.

    You can't go wrong with Honeywell however you should know that you may not have this functionality if you buy it from a big box store. Those thermostats are made to look the same as the ones professionals buy from the proper suppliers but have very limited functionality. When we come across them we know they are from a box store because their model number on the thermostat starts with an "R" instead of a "TH".

    If you have an option to hard wire the remote sensor to the thermostat then I suggest you do that. If that option isn't there to hard wire it then you can use the wireless ones.

    If you get a wifi capable thermostat then you can also adjust the temp from your phone if that helps you any.
     
  6. Dec 21, 2018 #6

    WyrTwister

    WyrTwister

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    That is the way I took it , too .

    Over all , it sounds like a bad idea , for more than one reason .

    God bless
    Wyr
     
  7. Jan 10, 2019 at 1:11 AM #7

    Diehard

    Diehard

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    I would ask why does he/she want to do this? For all anyone knows they may think they can control the upstairs and downstairs temperatures, separately.:eek::oops:o_O
     

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