Damp-Pi – Room Moisture Extraction with Raspberry Pi
Excessive humidity in the washroom is annoying and when you discover that your bathroom lacks the extractor fan, you rush to buy a fancy one with built in timers or humidity sensors. But there is an interesting way to avoid this problem. As explained by DAVEH, you can use a small computer to read the values from a humidity sensor in each room. Based on the reading, the fan can be turned on/off until the humidity is reduced to an acceptable level.
Daveh has used spare Raspberry Pi for this project but depending on your comfort, you can opt for Intel Edison, Intel Galileo, Creater CI20, Beagleone Black, Beaglebone green, etc.
Here’s a picture of the wiring before installation in the attic.
Certain equipment are used in this project and one of them is AM2302 Temperature and Humidity sensors. This will be placed near the ceiling of each shower room, where it can be easily wired up or you can secure the sensor to the wall with a small screw. Dual A/C Relay board is for the main power, which is needed for the wall mounted extractor fans.
Instead of opting for a complicated cable, everything is connected to the GPIO header on the Raspberry Pi. Therefore, it is broken down into simpler cables and with the help of a breakout board, everything is brought together. The sensors and the Relay board both require 5V power supply to activate and breakout board is responsible for distributing 5V and GND to each of the pin headers. Then you have only the data signal from the sensors, and two relay activation signals for the Relay board.
The mains components is isolated in a box with a cover and everything is mounted on a sheet of acrylic with stand-offs and the wires go straight up through the plasterboard.The software used for this project is a combination of a modelThingSpeak python script and Adafruit’sillustration for reading an AM2302, plus WiringPi and Wiring-Python to get-up-and-go the Relay GPIOs.
The temperature and humidity is published to ThingSpeak and can be read every minute. The same script is applied in each room and when the Humidity goes above 90%, fan is switched on and when it goes below 80%, the fan is switched off.
For more information, visit the following link-:
Filed Under: Reviews