Reptile Thermostat

This Arduino-based reptile thermostat is designed for terrariums to automatically control temperature and ensure a stable environment for reptiles. It features a DHT11 sensor to monitor temperature and humidity, an LCD display for real-time readings, and a relay module to switch heating elements on/off.

I created this project because commercial reptile thermostats can be expensive, and this DIY solution provides a cost-effective, customizable alternative. The special part of this project is that it uses a rotary encoder for easy temperature adjustments and an RTC module to differentiate between day/night heating settings.

Functions

✅ Monitors temperature and humidity using the DHT11 sensor.
✅ Automatically controls a heating element via a relay module based on temperature thresholds.
✅ Switches between day and night temperature settings using a real-time clock (RTC DS1302).
✅ Displays real-time temperature and humidity on an I2C LCD screen.
✅ Allows manual temperature adjustments using a rotary encoder with a push button.
✅ Includes a buzzer alarm to notify of temperature anomalies.
✅ Option to turn the display backlight on/off for night mode.

Hardware and Software Used

Hardware Components

• Arduino (Uno/Nano)
• DHT11 (Temperature & Humidity Sensor)
• Relay Module (For heating control)
• I2C LCD Display (16x2)
• Rotary Encoder with Push Button (For navigation and temperature control)
• DS1302 RTC Module (Real-time clock for day/night mode)
• Buzzer (For alerts)
• LED Indicator
• Insert Nuts & Screws (M2/M4)

Software

• Arduino IDE (For programming the microcontroller)
• Fusion 360 (For designing the 3D-printed case)

Wiring Diagram

A detailed wiring diagram is included for easy setup.

Code

The Arduino code reads data from the DHT11 sensor, checks temperature thresholds, and activates/deactivates the relay accordingly. It also manages user input from the rotary encoder and updates the LCD display.

Key Features of the Code

🔹 Reads temperature and humidity from the DHT11 sensor.
🔹 Uses the RTC module to switch between day and night temperature settings.
🔹 Allows users to adjust temperature using the encoder.
🔹 Displays real-time readings on the LCD.
🔹 Triggers an alarm if the temperature sensor fails.

📌 Full source code available on GitHub.

Printing Instructions

To 3D print the enclosure, use the following settings:

• Filament Material: PLA or PETG
• Layer Height: 0.2mm
• Infill: 20%
• Supports: No

Assembly Instructions

1. Print the enclosure using the provided 3D files.
2. Mount the components inside the case.
3. Wire the circuit according to the wiring diagram.
4. Upload the Arduino code to the microcontroller.
5. Test the system by adjusting the temperature and verifying the relay operation.

Demo and Usage Instructions

1. Power on the thermostat via USB or a 5V power adapter.
2. Use the rotary encoder to adjust temperature settings.
3. Check the LCD display for real-time temperature and humidity readings.
4. Relay will turn on/off automatically to maintain the desired temperature.
5. Press the encoder button to switch between settings.

📌 Full 3D models files available here:
🔗 Printables - Reptile Thermostat

This DIY reptile thermostat is an affordable, customizable, and reliable alternative to expensive commercial options. Hope you enjoy building it! 🦎🔥 Let me know if you have any questions! 🚀😊