In this project, the Sensuino works as a temperature controller (thermostat). It gets the information about temperature from DHT 22 module connected to D4 pin on the Sensuino shield, and controls it by cooler/heater attached to D2 pin through a magnetic relay. As we utilize the simple two state control (relay ON or OFF) we apply a hysteresis type control to avoid a faltering output state. This means that you will need to set the lower and the upper limit for temperature points. Temperature limit value and thermostat mode (heater – increases temperature in ON mode, cooler – decreases temperature in ON mode) could be set in the text menu implemented in the code which is accessible by holding one of the blue buttons.
Files to download
Arduino sketch: Thermostat.ino
Fritzing project: Thermostat.fzz