Climate Controller

This controller uses the Sensirion SHT11 combined temperature and humidity sensor.


 Measurement and Display: 
Scale selectable between Centigrade and Fahrenheit

Humidity 0 - 100% temperature compensated

Temperature -40 to 123 C (-40 to- 254 F)


Up to 3 DC switched outputs 10A or

2 DC outputs, 1 AC switched output (Max 4A)


Greenhouse temperature/humidity control

Small room temp/humidity control'

Hatchling warmer

Food dehydrating

The prototype

From clockwise top - DC board, Controller board, rotary encoder, SHT11 sensor and AC board.

Note the pcb in the photo for the controller board  is not the same as the final version available to order, or in the pcb download files. The DC board has been amended to include the reservoir capacitor  on the board.

 Click here for the project text and diagrams.


For stockists of the sensor see bottom of page.

The complete project file including the 'C' source code, hex file, parts list, schematic and PCB files in Eagle format can be found in the downloads section .

A preprogrammed PIC can be purchased for 5.00 inc P&P to most countries. The 3 PC boards are available either separately or as a bundle. Email projects@btech-online.co.uk for prices.


Sensor Stockists



This page copyright Colin Barnard 2004