Reference - Smart Thermostat Controlled HVAC Duct Damper


All firmware installed on particle photon WiFi - all particle components will respond when testing LEDs.

The temperature sensor is still reading 999.99, how do I test the sensor to make sure it is working properly or to program it to start reading actual room temperature? Also, the LED power light on the temperature sensor is dim when plugged into the “in” termination point but bright when plugged into the “out” termination point.

Thank you for your help.


Is there any way you can provide a photo of the temperature sensor/Photon setup you currently have? Many times I can find something quickly from good photos.


Sorry this may be an old thread. I’m trying to setup the Smart Thermostat controlled HVAC Duct Damper project but with the TMP112 sensor and I’m getting a temp reading of 999.99. What code do I need to change to get this project working with that type of sensor? Is it even possible?

Hi @oraclerouter

The duct thermostat project uses the MCP9803 as the temperature sensor. It pulls in a library I built for that sensor here:

I would recommend putting together a simple class library for the TMP112 that implements the same functionality as the MCP9803 and then just swap out the object in the Duct Thermostat project. That would be the simplest way to migrate to the TMP112.

If you are not experienced with programming/library development it may be simpler to just get an MCP9803.