It is difficult to maintain the appropriate temperature for a cultivation environment in the house because of the effect of outside air and sunlight. Improper conditions can hinder growth of crops and significantly affect the yield.

In this system, when an over-temperature condition occurs, usually in daytime, the digital control releases a cooling signal that sets off the circulation fan and cooling equipment bringing down the house interior temperature to the target value. Likewise, in supercool conditions, such as during winter or at nighttime, the digital controller releases a heating signal that sets off the heating equipment which agitates warm air inside the house through the circulation fan. Through this, the house interior temperature is maintained at a fixed value.

Furthermore, using the event output of the digital controller, the emergency alarm can be operated during high and low temperature, and an opening and closing function can also be added to the skylight window.