Three central air conditioning system facing hazard 1, harms - fouling fouling effect on the cooling effect can refer to Table 1. Table 1 shows the average thermal conductivity of the scale does not exceed 0.5-0.6 kcal / (m · h · ℃), only 0.15% copper, both of which were very different. Scale will affect heat transfer, which will bring two problems: First, reduce the cooling effect. Heat transfer film coefficient refrigerator condenser tubes are large front and back sides of Xuzhou air conditioning maintenance and fluoride, so the impact caused by fouling resistance scale of the overall heat transfer coefficient is particularly significant, the heat transfer performance. Figure 1 is a scale layer thickness (mm) and decrease the amount of energy consumption (%) relationship, Figure 2 is a dirt layer thickness (mm) and the total increase or decrease in unit cooling capacity (%) relationship. The figure shows, each 0.1 mm thick scale cooling capacity will be reduced by about 14%; secondly, condenser pressure will rise, leading to increased load, but consume more energy. 1 mm scale will consume energy 20-30%, high pressure will cause central air conditioner serious accident shut down the scale. First, the central air-conditioning units installed before the examination and preparation 1, according to the device specification packing list, certificate, inspection records and the necessary assembly drawings and other technical documents, check the model, specifications and all parts, components, materials and special tools subsidiary; Imported equipment must have test file inspection departments. 2, before installation should check the box, and the establishment of acceptance documented. Participants for the user, on behalf of supervision, construction and manufacturers (or distributors) and other parties. 3, after unpacking the unit to carefully check the surface, the host and parts and components, etc. Have the defect and rust, etc; whether the device is filled to keep gas leak, seal is intact; check after unpacking the equipment should take protective measures , premature or any removal to avoid damage to equipment; the equipment has any damage is found, please maintain the status quo in Xuzhou air conditioning maintenance and installation, and immediately notify the processing and marketing firms. 4. Check the supply voltage is consistent with the unit voltage, current, it should be able to meet the requirements of the unit. 5, in the concrete foundation reaches curing strength, smooth surface, location, size, elevation, etc. aside hole and embedded parts meet the design requirements after the Xuzhou industrial air-conditioning maintenance of telephone, before installation. 6, handling and lifting equipment, air conditioning maintenance, shall comply with the following requirements: (1) placing the device before installing the application pad to pad sound equipment; equipment should check the weight of the front (2) lifting, lifting tying solid, load-bearing power point equipment should be higher than the center of gravity; and (3) lifting with a common base unit, which does not cause stress points and deformation distorting the base unit. (4) the turning point of contact parts and equipment sling should be used soft material liner. (5) Note that when you can not make the lifting unit casing. Xuzhou Hitachi air conditioning sales, Sheng Erda refrigeration (certified), air-conditioning maintenance provided by Xuzhou 圣尔达 Refrigeration Electrical Services Limited. Xuzhou Sheng Erda Refrigeration Electrical Services Limited (xzktw.com) is in Xuzhou, Jiangsu, heat, refrigeration and air conditioning equipment leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customers needs. In Sheng Erda refrigeration leadership with the staff warmly welcome all inquiries negotiations to create a better future for refrigeration Sheng Erda.