Simple and reliable energy saving AC fresh air control scheme

The substance of AC fresh air control is that fully utilizes outdoor fresh air according to enthalpy of outdoor air, so achieves the goal of energy saving and improving indoor quality. The normal way is adjusting the amount of fresh air according to enthalpy which is calculated on the basis of temperature and humidity in and out door, this is called "enthalpy control". But because the cost of humidity sensor cell is high, its life is short, and it is very difficult to maintain, the long time and reliably running control systems are actually very short. However, all these shortcomings are overcome by the simple and reliable energy saving fresh air control scheme (SREFC). This paper discusses several fresh air energy saving control schemes, the SREFC scheme is suitable as regards general users, it only uses temperature sensor, and defines the nonsensical range according to the temperature of fresh air, local meteorological data and the vary range of humidity, so effectively utilizes outdoor fresh air and ensures the fresh air control system simply and reliably.