![My heat-only system only has two or three wires connected to the thermostat. Am I compatible with ecobee? My heat-only system only has two or three wires connected to the thermostat. Am I compatible with ecobee?](https://storage.googleapis.com/article_attachments/227874667/gasvalvefaststat.png)
My heat-only system only has two or three wires connected to the thermostat. Am I compatible with ecobee?
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Honeywell Home Wi-Fi Smart Color 7-Day Programmable Smart Thermostat with Color-Changing Touchscreen Display RTH9585WF - The Home Depot
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Old Honeywell 2 wire AC thermostat (with 1 extra wire behind) - can I modernize this with Ecobee? : r/ecobee
![heating - Wifi thermostat to replace old mechanical 2-wire 110V Honeywell? - Home Improvement Stack Exchange heating - Wifi thermostat to replace old mechanical 2-wire 110V Honeywell? - Home Improvement Stack Exchange](https://i.stack.imgur.com/YnlT0.jpg)
heating - Wifi thermostat to replace old mechanical 2-wire 110V Honeywell? - Home Improvement Stack Exchange
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Two 2 wire Honeywell digital thermostat to replace mercury switch. Convert from mercury switch - YouTube
![Trying to replace this old 2 wire thermostat for a newer digital one. Problem is older unit does not have leads labeled or which cable is which. Any help on how to Trying to replace this old 2 wire thermostat for a newer digital one. Problem is older unit does not have leads labeled or which cable is which. Any help on how to](https://i.redd.it/j9mnonzn7nu91.jpg)
Trying to replace this old 2 wire thermostat for a newer digital one. Problem is older unit does not have leads labeled or which cable is which. Any help on how to
![N1 Common C Wire Adapter AC Transformer 24V 500mA Universal Compatible With WIFI Smart Thermostat and Doorbells. Nest, Ring, Honeywell, Ecobee, Sensi - White, New - Walmart.com N1 Common C Wire Adapter AC Transformer 24V 500mA Universal Compatible With WIFI Smart Thermostat and Doorbells. Nest, Ring, Honeywell, Ecobee, Sensi - White, New - Walmart.com](https://i5.walmartimages.com/seo/N1-Common-C-Wire-Adapter-AC-Transformer-24V-500mA-Universal-Compatible-With-WIFI-Smart-Thermostat-Doorbells-Nest-Ring-Honeywell-Ecobee-Sensi-White-Ne_f8863ff8-f2ff-4a3d-9a67-38e8bdd5be59.6d13dff0e6b9cea7329179d188ec79bf.jpeg?odnHeight=768&odnWidth=768&odnBg=FFFFFF)
N1 Common C Wire Adapter AC Transformer 24V 500mA Universal Compatible With WIFI Smart Thermostat and Doorbells. Nest, Ring, Honeywell, Ecobee, Sensi - White, New - Walmart.com
![6 things you should do before you replace your current thermostat with a smart thermostat – Smart Thermostat Guide 6 things you should do before you replace your current thermostat with a smart thermostat – Smart Thermostat Guide](https://smartthermostatguide.com/wp-content/uploads/2018/07/old-thermostat-tips-for-replacing-with-smart-thermostat.jpg)
6 things you should do before you replace your current thermostat with a smart thermostat – Smart Thermostat Guide
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Honeywell THX9421R5021WW 2 Wire IAQ High Definition Touch Screen Thermostat with Red LINK Technology, White: Amazon.com: Tools & Home Improvement
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