SHT41 ESPHome¶

A simple ESPHome configuration for reading temperature and humidity from an SHT41 sensor and publishing the data over MQTT.

What you need for this specific project¶

an SHT41 sensor (and extra wires depending on your model)

Pin layout¶

Note

ESP32 boards allow flexible I2C pin assignment. My pin layout isn't set in stone, you can change it.

ESP32 Pin	SHT41 Pin	Description
3V3	VIN	Power
GND	GND	Ground
GPIO3	SCL	I2C Clock
GPIO2	SDA	I2C Data

ESPHome¶

ESPHome supports OTA (Over the air) updates, so I don't need to touch it at all to update the code.
However, it uses YAML not .ino code so that changes.

This code publishes to the MQTT topic sensors/sht41/humidity and sensors/sht41/temperature. Adjust it according to your needs.
This code takes readings from the SHT41 sensor every 2 seconds continuously.

Variables

To change the topic it publishes to, change topic_prefix under mqtt: and the two state_topic: under sensor:
If you have a different model, change the board to match.
Replace ssid and password with your WiFi SSID and password.
Replace server_lan_ip with your servers local IP address.

If you deviated from my pin layout, change scl and sda here too.

esphome:
  name: sht41-c3
  friendly_name: SHT41 ESP32-C3

esp32:
  board: nologo_esp32c3_super_mini
  framework:
    type: esp-idf

logger:

#api:
#  encryption:
#    key: !secret api_encryption_key

ota:
  - platform: esphome
    password: ""

wifi:
  ssid: "ssid"
  password: "pass"

  ap:
    ssid: "SHT41-C3 Fallback"
    password: "esp32c3test"

captive_portal:


mqtt:
  broker: server_lan_ip
  port: 1883
  topic_prefix: sensors
  client_id: sht41-c3

i2c:
  sda: 2
  scl: 3
  scan: true

sensor:
  - platform: sht4x
    temperature:
      name: "temperature"
      id: sht41_temp
      state_topic: sensors/sht41/temperature
    humidity:
      name: "humidity"
      id: sht41_hum
      state_topic: sensors/sht41/humidity
    address: 0x44
    update_interval: 2s

After editing the YAML, use esphome run <filename>.yaml to push the updates.

Expected output¶

My bad, I did not record data over Serial. So your only point of reference is live data over MQTT.

Monitoring & Troubleshooting¶

If something isn't going according to plan, you can open up the Serial Monitor in Arduino IDE and see what may cause the issue.
Also, you can view the Mosquitto and Telegraf containers logs to check there too.