> ## Content Index > Fetch the complete content index at: https://broddin.be/llms.txt > Use this file to discover other available public pages before exploring further. # A house full of sensors with ESPHome - URL: https://broddin.be/a-house-full-of-sensors-with-esphome/ - Published: 2021-01-15T07:00:00.000Z - Updated: 2026-07-19T19:05:18.000Z - Author: Tim Broddin - Tags: esphome, #english, #wordpress, #Import 2024-02-03 13:15, #broddin, #Migrated-1784487752640, #wp, #wp-post, #Import 2026-07-19 19:02 These days you can waste a lot of money on **smart appliances**. Or make such smart devices yourself. ## ESP As I said in my previous article about [our staircase with 600 LED](https://broddin.be/2021/01/05/how-i-turned-the-stairwell-into-a-nightclub/)s, **Espressif ESP** boards are ideal for when you want to make things that connect to the Internet: Luckily other development boards are very good at that. Those boards contain the **ESP8266** microchip. That chip can be programmed in the same way as an Arduino but has **built-in WiFi** and the necessary libraries to enable IoT applications. His big brother, the ESP32, is also equipped with Bluetooth (and is twice as fast). ## Go big or go home This is what I made with my very first ESP8266 board: ![](https://broddinblog.on-forge.com/storage/447/img-9928.jpg) Many wires, a motion sensor, a light sensor, a microphone, a temperature and humidity sensor, a screen, and a laser beam. This thing is still hanging up in our meeting room at VRT and, of course, is **total overkill** to see whether the lights are on. I put **way too much time** into it at the time, but it taught me how to connect an ESP to the network and also the principles of [MQTT](https://mqtt.org/?ref=broddin.be) and [node-red](https://nodered.org/?ref=broddin.be). Everything these sensors capture is forwarded every 10 seconds to an MQTT server (a kind of telephone exchange for IoT applications), which communicates it to a small application that I wrote in node-red. ![Someone pulled the plug during this pandemic.](https://broddinblog.on-forge.com/storage/448/screenshot-2021-01-14-at-094204.jpg) Someone pulled the plug during this pandemic. Little did I know there’s already a project that does everything I did and more: **ESPHome**. ## ESPHome ESPHome is a system to control your ESP8266/ESP32 by simple yet powerful configuration files and control them remotely through Home Automation systems. In short, ESPHome is a firmware for ESP that allows you to create things like the above without writing any code and integrates with Home Assistant and others. After installation (`pip3 install esphome`), you can quickly start a new project via the wizard (`esphome serverkast.yaml wizard`), and after answering some questions, the wizard writes out a YAML file containing the minimum configuration: ```yaml esphome: name: serverkast platform: ESP8266 board: nodemcuv2 wifi: ssid: "" password: "" Enable fallback hotspot (captive portal) in case wifi connection fails ap: ssid: "Sample Fallback Hotspot" password: "" captive_portal: Enable logging logger: Enable Home Assistant API api: ota: ``` When you **flash** this on your ESP (`esphome run serverkast.yaml`), your ESP will reboot, connect to your WiFi network and appear in Home Assistant. Of course, this does absolutely nothing. So it’s time to connect some **sensors**. Inside my server cabinet, there is an ESP8266 with a DHT11 temperature and humidity sensor connected to PIN D2\. In the configuration file, this becomes (beneath `ota:`): ```yaml sensor: - platform: dht pin: D2 model: DHT11 temperature: name: "Serverkast Temperature" filters: - calibrate_linear: - 0.0 -> 0.0 - 24.0 -> 23.5 humidity: name: "Serverkast Humidity" update_interval: 60s ``` (Because DHT11 temperature sensors are cheap but **not precisely accurate**, a small calibration occurs: 24 degrees is adjusted to 23.5.) After reflashing (via USB or over WiFi), these sensors appear in **Home Assistant**: ![](https://broddinblog.on-forge.com/storage/449/screenshot-2021-01-14-at-100948.jpg) In Home Assistant, the data from these sensors can now be used to perform **automations** or to create beautiful graphs using, for example, [InfluxDB](https://www.influxdata.com/?ref=broddin.be): ![Our radiator broke down while we were away …](https://broddinblog.on-forge.com/storage/450/screenshot-2021-01-14-at-101143.jpg) Our radiator broke down while we were away … ## Sensors, buttons & screens The great thing about ESPHome is that **everything you can think of** works out of the box. Hang an e-paper display on it? A camera? Or create your own IR remote control? It’s all possible, and it all works through the same configuration file. You can find an overview of all supported components [here](https://esphome.io/components/index.html?ref=broddin.be). ## Automations in ESPHome An automation I have planned for the ESP8266 in my server cabinet is to automatically start a fan when the temperature is higher than 30°. You can do this in the Home Assistant interface but also in the configuration file itself: ```yaml sensor: - platform: dht pin: D2 model: DHT11 temperature: name: "Serverkast Temperature" filters: - calibrate_linear: - 0.0 -> 0.0 - 24.0 -> 23.5 on_value_range: - above: 30.0 then: - fan.turn_on: fan - below: 30.0 then: - fan.turn_off: fan ``` The latter has the advantage that your automation works even when Home Assistant is not accessible and is especially recommended for **simple automation** that does not require other devices in your network. ## Automations in Home Assistant During the Christmas period, I connected an ESP with some LEDs (I didn’t know WLED at that time) and a button. When you hit that button, our Google Nest Hub started playing **Christmas music**, and the lights turned on. ESPHome To do this, the ESPHome sends an **event** to Home Assistant: ```yaml binary_sensor: - platform: gpio pin: number: D0 mode: INPUT_PULLDOWN_16 name: "Button" on_press: then: - homeassistant.event: event: esphome.button_pressed data: title: Button was pressed ``` Home Assistant sets the Nest’s volume to 75%, selects a random Christmas song, lights on, and turns on the Philips Hue’s Cozy scene. ```yaml - id: '1608044655971' alias: Play xmas description: '' trigger: - platform: event event_type: esphome.button_pressed condition: - condition: device type: is_off device_id: 3a18233816ee484b9780e3448c416fec entity_id: light.xmas_leds domain: light action: - service: media_player.volume_set entity_id: media_player.woonkamer data: volume_level: '0.75' - service: media_player.play_media data: media_content_type: music entity_id: media_player.woonkamer data_template: media_content_id: '{{ [ "http://www.edsstuff.org/Music/Christmas/Disney/Disc%20A/14-White%20Christmas.mp3", "http://news.bpmsupreme.com/wp-content/uploads/2015/12/Mariah-Carey-All-I-Want-For-Christmas-Is-You-Clean.mp3", ] | random }}' - type: turn_on device_id: 3a18233816ee484b9780e3448c416fec entity_id: light.xmas_leds domain: light brightness_pct: 50 - service: hue.hue_activate_scene data: group_name: Living scene_name: Gezellig ``` Be careful if you make something like this, and you have kids. You’ll get tired of this very quickly. ## Update ESPHome in Home Assistant After the first flash via USB, your ESPHome can update **OTA** (over-the-air – over WiFi). This is useful because it allows you to keep your sensors where they are and still make configuration changes. In Home Assistant, you also have an [ESPHome community add-on](https://esphome.io/guides/getting%5Fstarted%5Fhassio.html?ref=broddin.be). It contains the latest version of ESPHome and allows you to perform updates from the Home Assistant interface. ![](https://broddinblog.on-forge.com/storage/451/screenshot-2021-01-14-at-104201.jpg) I always copy my configuration files here after flashing via USB. This allows updating wherever possible and gives easy access to my various devices’ logs and status. ## The result I want to do some crazier things with ESPHome in the future, but I keep the temperature and humidity for now. ![](https://broddinblog.on-forge.com/storage/452/screenshot-2021-01-14-at-120523-1.jpg)