Fan only temp setting

[Sjedward48]

I am looking to purchase a nest thermostat for my house but before I do I want to see if I can set it up the way I need. I need to be able to to set a temp for the fan to come on as if it were heating. I have an oil fired forced air furnace with a water to air heat exchanger in the plenum that brings hot water in from my outdoor boiler. I want to be able to turn on the fan without kicking the oil furnace on and circulate heat through my heat exchanger 

[zoeuvre]

Hi Sjedward48, 

Thanks for posting here in the Community forum. Firstly, are you located in North America or Europe? 

Second, Nest Thermostat will let you set a schedule for the fan that doesn’t depend on heating or cooling your house. The system allows you to define the fan on and off time when you do not want the heating and cooling system to operate. This ensures the air flows through the heat exchanger without triggering the oil furnace. Ensure that the wiring of your HVAC system is capable of supplying a separate fan control wire. The Nest thermostat has to have a connection to the fan wire in order to control the fan independently. In the course of Nest thermostat installation, you can program the wiring and install the fan control. Connect and configure the fan wire following the instructions from the Nest app or installation guide. This will allow you to operate the fan independently.

Lastly, setting up a fan schedule involves downloading the Nest app to your smartphone or tablet or using the Nest thermostat to create a fan schedule. Set up the time periods during which you wish the fan to operate and indicate your preferred target temperature. Then, your thermostat will switch on your fan during those designated times, enabling your heat exchanger to eliminate the heat without activating your oil furnace. Learn more about this here in the Fan control with a Nest Thermostat article.

Keep us posted. We're happy to help.

Best,

Zoe