Home Assistant

Xiaomi Mijia thermometer & hygrometer in Home Assistant (LYWSD03MMC) on Hass.io

Connecting a thermometer & hygrometer (humiditymeter?) to Home Assistant can be a bit of a hassle. Who doesn’t want one in every room? There are lots of ways to get them set up, but it’s easy to make things nicely-complicated & expensive. Who doesn’t love spending more money than you need? I picked up a pack of Xiaomi Mijia sensors (or LYWSD03MMC, when you get to know them), they run on a coin-cell battery for about a year, have BTLE / Bluetooth Low Energy transmission of their status, and are pretty cheap.

Setting up MQTT with Auto-Discovery on Home Assistant (settings)

After you’ve installed things for MQTT in Home Assistant, it’s time to make some settings. 1. Enable debug logs. I don’t actually have much insight into what this does, but whatever. It sounds good. I did it. It didn’t hurt. In the configuration.yaml file (see previous post for information on how to edit files), add: logger: default: warning logs: homeassistant.components.mqtt: debug … and then reload the settings by restarting. Configuration -> Server Controls -> Check Configuration.

Setting up MQTT with Auto-Discovery on Home Assistant (software setup)

MQTT on Home Assistant is one of the most annoying things to figure out. The documentation is extremely minimal, their forum is filled with links to the documentation when people ask about not being able to understand the documentation. I’m keeping notes & warnings here. There are a few elements of MQTT that are important for this. You might already have some of this set up, if you followed some general Home Assistant getting started guides.