Smart Thermostat Automation with MQTT and Node-RED

General
1

I recently set up a smart thermostat system using MQTT and Node-RED, and I wanted to share my experience and some tips for anyone looking to do something similar. :thermometer:

The Setup
I have a Tuya IR blaster controlling my AC heater, and I use MQTT to track both the solar panel output and the AC’s status. My goal was to automate the AC based on solar energy production, but I ran into a common issue: the AC would beep every time it received an IR signal, even if it was already on. :sweat:

The Challenge
The automation was sending signals to the AC regardless of its current state. For example, if the AC was already on and the solar output indicated it should stay on, it would turn on again, causing that annoying beep every minute. I realized I needed a way to check the AC’s current state before sending a command.

The Solution
After some research, I discovered that using a function in Node-RED to check the MQTT topic for the AC’s current state was the way to go. Here’s a simplified version of what I did:

javascript
function checkACState() {
const acState = msg.payload.topicState;
const solarOutput = msg.payload.solarOutput;

if (acState === “on” && solarOutput >= 900) {
return { payload: “off” };
} else {
return { payload: “on” };
}
}

This function checks if the AC is already on and if the solar output meets the threshold before sending a command. It eliminated the unnecessary beeps and made the system much smoother! :tada:

Tips for Others

  1. Use MQTT for State Tracking: MQTT is great for real-time updates. Make sure to set up topics for both sending and receiving device states.
  2. Test Functions Thoroughly: Before integrating, test your functions with dummy data to ensure they handle all possible states correctly.
  3. Consider Polling Intervals: If your system is too reactive, it might cause unnecessary wear and tear. Adjust your polling intervals based on your devices’ needs.

Final Thoughts
This project taught me the importance of checking device states before automation commands. It’s a small detail that makes a big difference in user experience. If anyone has questions or wants to share their own automation tips, I’d love to hear them! :rocket:

Happy automating! :star2: