ESPHome

ESPHome devices are configured as YAML files under esphome/ in the HA repository and managed via the ESPHome dashboard.

Apollo Air-1

Two Apollo Air-1 sensors monitor air quality — one in the bedroom and one in the office. Each sensor measures:

The sensors also have an RGB LED used as a local visual indicator — for example, turning orange when CO2 levels are elevated (triggered by a Home Assistant automation).

Bluetooth proxies

Three ESP32 devices act as Bluetooth proxies, extending Home Assistant's Bluetooth range throughout the home. The living room proxy (Olimex ESP32-POE-ISO) connects via Ethernet; the bedroom and office proxies use Wi-Fi.

The proxies are used primarily with Xiaomi Mi Flora plant sensors, which communicate over Bluetooth LE.

RuuviTag Pro

A RuuviTag Pro in the sauna reports temperature over Bluetooth. Home Assistant sends a push notification when the sauna is ready.

My experience

The Apollo Air-1 sensors have worked well. They were expensive, but the accuracy justifies the cost — for example, they pick up PM2.5 spikes when cooking.

The Bluetooth proxies have been reliable with the plant sensors. Matter support for plant sensors has been announced but no products are available yet.

The RuuviTag in the sauna works well, though it can't handle the highest temperatures so it's mounted at bench height rather than near the ceiling. It doesn't report the actual sauna temperature directly, but its reading is enough to tell when the sauna is warm — Home Assistant sends a notification at that point.