Control methods; DDC controller outlet temperature or room temperature sensor measures the temperature in accordance with the new fan and setpoint deviation compared with PID law regulating cold / hot water valve opening in order to control the freezing (heating) water tank air conditioning units, so that the room temperature is below summer 28 ℃, winter is higher than 16 ℃. Feedforward compensation to eliminate the use of pre-impact outdoor air temperature change on the output. During the transition season, you can stop for regulating air temperature to save energy. When the filter infarction or when its value beyond the rules, given the pressure switch switch signal. When demand for cooling, refrigeration thermostat placed in the form, when the temperature sensor measurements at or below the set temperature, the thermostat valve to the electric signal a closed valve, close the valve contacts the valve is turned on the electric valve closed . If the measured temperature does not reach the set temperature heat recovery air-conditioning unit, thermostat valve is an open valve to the electric signal, the electric valve open contacts connected valve open. When heating demand ceiling air conditioning units, heating thermostat set form, when the temperature sensor measurements at or above the set temperature air conditioning unit, a thermostat valve off valve to the electric signal, the electric valve contact the valve is turned off valve closed. If the measured temperature does not reach the set temperature, the thermostat valve is an open valve to the electric signal, the electric valve open contacts connected valve open. ZK modular air conditioning units, Chen Yu-conditioned factory outlets (certified) Pingdingshan City air conditioning units provided by Wu Chen-yu air-conditioning Limited. Wu Cheng Chen Yu Air Conditioning Equipment Co., Ltd. (www.wccykt.com) is a leader in Dezhou, fans, ventilation equipment, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs . Chen Yu-conditioning in leadership with the staff warmly welcome all inquiries negotiations to create Chenyu conditioning a better future.