![Installing new 2-wire (Single Pole) Thermostats - how to install when there are 3 wires in wall? - Home Improvement Stack Exchange Installing new 2-wire (Single Pole) Thermostats - how to install when there are 3 wires in wall? - Home Improvement Stack Exchange](https://i.stack.imgur.com/JmTci.jpg)
Installing new 2-wire (Single Pole) Thermostats - how to install when there are 3 wires in wall? - Home Improvement Stack Exchange
![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/Untitled_Diagram__10_.png)
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? 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/gasvalvediagram.png)
My heat-only system only has two or three wires connected to the thermostat. Am I compatible with ecobee?
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hvac - How can I modify a 4 wire thermostat to a new thermostat requiring c wire? - Home Improvement Stack Exchange
![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/rwcdiagram.png)