Features: There are four types of ZK a/c composite units, i.e. clean type, commercial type, low temperature type and Outdoor type, which can be separately used to meet the requirements of the factories such as micro-electronics, biological pharmacy, precise instrument industries. Clean type: according to the standard, the interior wall is stainless steel or galv. steel plate and there is s special treatment for the filtration and sealing. Commercial type: It is a comfortable a/c unit to meet the requirements of the commercial buildings and industrial plants. Low-temperature type: used together with ice storage refrigerate and lower temperature refrigerate agents, the cooling capacity per unit is bigger. The insulation and anti-cold bridge has been specially treated.Outdoor type: It is suitable to be used in the open. Rain and snow proof performance of the product has been considered and the rust proof of the whole set has been practically treated. Several patents are used in the frame structure of the ZK series products so that the product quality is guaranteed. The Patent Nos. for the materials to be used. The design of the frame structure of the composite units are as follows: (ZL 96 3 11945.1, ZL 99 3 33068.1, ZL 99 2 39204.7, ZL 00 2 67019.4, ZL 01 2 45223.8) The part of door plate under positive pressure is fixed from inside to outside to improve the sealing performance when running due to the function of the interior positive pressure, but the part of the door plate under negative pressure is fixed from outside to inside so that the sealing performance is improved when running due to the function of the interior negative pressure. The structure is designed to be dismantled and assembled very fast and can be installed in a narrow space with no adverse quality effect. There is a laminated structure set for design consideration, which can save space area and investment as well.There are several function sections to be combined in the unit to meet different requirements of industries. For instance: heat receiving section in the A/C set can save energy when used in the labs for animals and/or organisms.The high effective smoke filter section and multi-layer composite filter and sprinkling filter section can be successfully used in the tobacco industry. The cold water sprinkling section or heat moisture treatment can be used in the textile industry. For the small purifying system, the unit with constant temperature and constant humidity can be used by direct evaporating.The above-mentioned function sections can be designed and made in accordance with the customer's requirements. There are not much touch in this handbook. According to the customer's requirements, it is possible to provide frequency control device or VS electronic speed motors or fully auto control system. DDC communication outlets can be preserved.