rsenykoff / esp8266mqttdht22

ESP8266 Publish Temperature / Humidity Sensor Data to MQTT

Updating my code for use with AWS IoT Core

This was developed on an Adafruit Huzzah ESP8266 Wifi.

• Periodically check Temperature and Humidity Settings
• Maintain a Wifi Connection to your network
• Maintain MQTT Connection and Publish using your designated queues

Hardware

• DHT22 Temperature and Humidity Sensor
• Adafruit Huzzah ESP8266 Wifi

Software

• Arduino IDE
• Adafruit MQTT Library
• Adafruit DHT Sensor Library

This project assumes you already have an MQTT server up and running on your network. Testing was done with Mosquitto MQTT running on Ubuntu.

I currently use this with OpenHAB open-source home automation server. OpenHAB can be configured to subscribe to a Mosquitto message queue and use rrdtool to log the data over time. I can move this sensor around the house, and track the heating / cooling. This was useful to figure out how early to have the digital thermostat in our bedroom turn on in order to hit a target temperature when we wake up. Devices like the Nest will do this automatically for you, but this is a lot cheaper. :)

You may recognize this chart style if you're familiar with RRDTool. That's what OpenHAB is using under the hood to store this. The chart says bedroom humidity, but this is me measuring the cellar where the furnace is located. So you'll notice when the furnace is running the temperature rises and the humidity drops.