Build This Automatic Thermostat to Control Your Wood Stove

Most homes in the United States are heated with natural gas, and virtually all gas furnaces are designed to be controlled by a thermostat in order to keep the air inside the house at a relatively constant temperature. But if you have a wood stove, you likely don’t have that luxury. The only way to regulate the temperature is to manually open or close the stove’s damper. If you want the convenience of automated control, you can follow NESCustomDesign’s tutorial to build a thermostat for your wood stove.

Basic gas furnace thermostats are extremely simple: if the current temperature is lower than the desired temperature, they turn the furnace on. If it’s higher than the desired temperature, they turn the furnace off. NESCustomDesign’s wood stove thermostat works in a similar way. The major difference is that instead of turning the stove on or off, it opens or closes the damper in order to regulate the heat output. That was accomplished using just a handful of inexpensive IoT components that are easy to find.

This thermostat can be thought of as two separate devices: the display unit where you set the temperature, and the motor unit that actually actuates the stove damper. The display unit is built with a Wemos D1 Mini ESP8266 development board, and includes a DHT11 temperature and humidity sensor and a 16x2 character LCD display. The motor unit is controlled by a NodeMCU ESP8266 board, and controls the stepper motor through an EasyDriver motor driver. Both units are housed within 3D-printed enclosures. NESCustomDesign is using the Blynk IoT service to control the units, but you can use whatever service or custom-programmed behavior you like. With the Blynk service, you can set the temperature on the display unit or remotely over the internet with an app.