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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 5648
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I am trying to upgrade from a VERY old thermostat (building

Customer Question

Hello! I am trying to upgrade from a VERY old thermostat (building is 1968 construction and would not be surprised if this original equipment). Terminals are numbered 4,5,6. Looking for corresponding letters on the new digital unit I bought years ago and found in my closet.
I put some reference shots on Google and you should be able to see them at:
Any chance you can help?
Submitted: 29 days ago.
Category: HVAC
Customer: replied 29 days ago.
please respond by email to***@******.***
Expert:  Webb-Guy replied 29 days ago.

Hello and welcome to just answer my name is ***** ***** I will be the one who will try to assist you today. Any chance you can take a picture of where the furnace and the thermostat wires come together. Also what unit are you replacing it with?

Customer: replied 29 days ago.
I assume the link to Google Picassa did not work. I'll upload the files. Give me a minute.
Expert:  Webb-Guy replied 29 days ago.

i need to see which wires are going into the furnace. The google picasa worked.

Customer: replied 29 days ago.
I am taking more reference shots. Will take a few minutes to upload, then I will update the Google album.
Customer: replied 29 days ago.
Album updated
Expert:  Webb-Guy replied 29 days ago.

ok those wires do not match whats inside your thermostat. So someone has broke the wires off in the back of the wall and I will have no way to walk you through this. The furnace has red and yellow wires in it but they are not on the thermostat. So I wont be able to walk you through this. I will opt out.

Customer: replied 29 days ago.

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