Re-understanding of HVAC climate characteristics in hot summer and cold winter zone

 Hot summer and cold winter zone is one of the climate zones of building thermal design, mainly focusing on the dry-bulb temperature of outdoor air, which can not be used as the climate zone of HVAC system design. Based on the indoor thermal comfort grade standard stipulated in GB 50736-2012 Design code for heating, ventilation and air conditioning of civil buildings, divides outdoor air states into nine regions in psychrometric chart. For nine representative cities in hot summer and cold winter zone, calculates the distribution hours of outdoor air thermal and humidity state in nine regions of the psychrometric chart, analyses the annual variation process of outdoor air thermal and humidity state of each representative city, and preliminarily obtains the annual seasonal composition and division of the hot summer and cold winter zone. Further analyses the climate difference between east and west regions. In order to more specifically develop and apply building thermal environment control technology and improve energy efficiency, it is advisable to divide the hot summer and cold winter zone into two HVAC climate zones, with the plain climate zone in the east and the mountain climate zone in the west.