Antifreeze and interlock in winter outdoor design temperature is below 0 ℃, you should consider freezing problems coil. In addition to the air conditioning system design preventive measures should be adopted in itself, from electrical and control unit, it should adopt certain measures. 1) limit the hot coil electric valve minimum opening in coil selection to meet certain requirements of the situation, in order to limit the hot coil electric valve minimum opening. Especially for the two control system of hot and cold dual-coil, especially, after the minimum opening should be set within the coil to ensure the water does not freeze the minimum amount of water Wmin; 2) Set the temperature control which is to prevent freezing during operation Another measure of the cracking coil. Usually in hot water outlet pipe plate (or coil on backwater even me) to set up a temperature sensor (controller), measuring the return water temperature. When they measured values ??as low as about 5 ℃, frost controller action to stop the air conditioning unit to run a new unit, at the same time to open a large hot water valve. Technical performance of new air handling units (1) technical performance table is under atmospheric pressure 760mmHg case calculation. When used in other areas below the atmospheric pressure, the cooling capacity with decreased atmospheric pressure and slightly increases. Therefore, new air unit cabinet, when using this sample data is more secure. (2) the general air conditioning (15% fresh air) means: new air handling units offer when cooling, into the wind, dry mouth bulb temperature of 27 ℃, into the wet bulb temperature of 21 ℃, when heating fresh air unit type, into dry bulb temperature is 20 ℃ . (3) Fresh Air (100% fresh air) means: when cooling, into the dry bulb temperature of 34 ℃, into the wet bulb temperature of 28 ℃. When heating, into the dry bulb temperature of -4 ℃. (4) cold water temperature: Water 7 ℃, backwater 12 ℃, hot water temperature is 55 ℃, backwater 45 ℃. Ceiling fresh air unit, Rui Xincheng air conditioning (certified), Yan'an new air handling units provided by Rui Xincheng Air Conditioning Equipment Co., Texas. Texas Rui Xincheng Air Conditioning Equipment Co., Ltd. (www.dzrxckt.com) is a leader in Dezhou, fans, ventilation equipment, over the years, the company implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs . Rui Xincheng conditioning in leadership with the staff warmly welcome all inquiries negotiations to create a better future Rui Xincheng air conditioning.