ESP32 DHT22 Telegram Bot

A real-time IoT project using ESP32 + DHT22 to monitor temperature and humidity and send data via a Telegram bot.

🔥 Features

• 🌡 Temperature & 💧 Humidity monitoring
• 🤖 Telegram bot commands
• 📊 Live system status (/data)
• 😄 Smart “feel” messages (/feel)
• 🔐 Secure (only allowed users)
• ⚡ Async & non-blocking design
• 🧠 Moving average filtering for stable readings

📸 Hardware Setup

ESP32 Dev Board + DHT22 Sensor

Wiring:

it requires 3 Jumper Wires

DHT22(sensor)	 ESP32(module)

+       3V3  
-       GND  
OUT      D4  

⚙️ Setup

1. Install Arduino IDE
2. Install ESP32 board support
3. Install ESP32 Board in Arduino IDE
4. Open Arduino IDE

Go to:
File → Preferences

Add this URL in Additional Board Manager URLs:
https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json

Go to:
Tools → Board → Boards Manager
Search: esp32
Install: esp32 by Espressif

5. Install Libraries (Go to Library Manager)

DHT sensor library (Adafruit)
UniversalTelegramBot
ArduinoJson

6 - Select Your Board

Tools → Board → ESP32 Dev Module
Tools → Port → /dev/ttyUSB0  (or similar)

🤖 Telegram Bot Setup

• Open Telegram → @BotFather
• Run:

/newbot

• Copy your BOT TOKEN

🔑 Configuration

Choose Anyone of the Code below based on your usage:

• esp32_dht22_telegram_bot.ino: for faster response and consume more energy
• esp32_dht22_optimized_bot.ino: Optimized and deplay in bot response (recommended)
• esp32_dht22_web_bot.ino: Telegram Bot + web view with Real-time Live Data + Telegram Trigger Button (recommended)

Edit the code:

const char* ssid = "YOUR_WIFI_NAME"; // it support 2G WIFI Only
const char* password = "YOUR_PASSWORD";
const char* BOT_TOKEN = "YOUR_BOT_TOKEN";
const char* ALLOWED_IDS[] = {
  "YOUR CHAT ID"
};

🚀 Upload

• Select ESP32 Dev Module

Tools → Board → ESP32 Dev Module
Select Port : /dev/ttyUSB0

• Upload via Arduino IDE - Click Upload

📱 Telegram Bot Commands

• Command Description

start - 👍 Start the bot
data - 🔌 Show system + sensor status
feel - 😛 Funny weather feeling
temperature - ☀️ Get temperature
humidity - 🔥 Get humidity

⚠️ Notes

• DHT22 updates every ~2 seconds (hardware limitation)
• Use 3.3V (not 5V)
• Avoid rapid polling

Credits

• Room temperature and humidity with ESP8266, DHT11, and a Telegram bot - https://github.com/mcnaveen/esp8266-dht11-telegram
• Universal Telegram Bot Library - https://github.com/witnessmenow/Universal-Arduino-Telegram-Bot
• ESP32 and DHT22: Learning Hardware Selection the Hard Way - https://medium.com/@ummugulsun/esp32-and-dht22-learning-hardware-selection-the-hard-way-49d2589050c2
• Youtube Demo Video: https://www.youtube.com/shorts/qvT4jK5xQgs

LICENSE

MIT License