Common symptoms of central air conditioning (1), drain: refers to refrigerant leakage; electrical (wiring, body) leakage and other damage caused by the insulation. (2), block: refers to fouling and plugging the ice refrigeration system; air filter is clogged; air inlet and outlet are an obstacle blockage. (3) off: an electrical line break; fuse blown; due to overheating or excessive current overload caused by the contact is open; the cooling system pressure caused by abnormal pressure switch contact is opened and the like. (4), burn: refers to the compressor motor windings, fan motor windings, solenoid coils, relay coils and contacts, etc. are burned. (5), the card: a compressor means jammed, jammed fan, moving parts of bearings jam. (6) damage: broken finger compressor valves, piston scuffing, fan blade fracture and various parts breakage. On refrigeration engineering of refrigeration oil: 1, compressor lubricants in refrigeration engineering usually called frozen oil, which plays an important role in the operation of the refrigeration compressor. Under normal circumstances, oil change air-conditioning unit is factory run a cooling season (or heating season) to replace the oil once and then replaced periodically depending on the operating conditions. Because the unit during the assembly process, in order to prevent further leakage point second-hand air conditioning, the use of welding methods Xuzhou hand air conditioning repair, welding nitrogen welding process, but the filling of the nitrogen pressure is not big, big welding tainted point , the presence of air in the case of welding, there are a lot of scale exist in the system, such as the scale of the refrigerant in the system operation, it can hinder the transportation of oil from the points of the compressor rotor wear Xuzhou Used central air conditioning recovery, there may be clogged oil capillary, causing the unloading system failure, resulting in the unit normal operation can not be stable; 2, refrigeration compressor with lubricating oil during operation, lower compressor temperature, between acting parts of hermetic compressors gaps and provide add, subtract load function, so, kinematic viscosity refrigeration oil, small amounts of moisture, copper corrosion, acid number and insoluble material must meet the standards. Through years of detection test, summed run need to be replaced once a year, time is running short in the northern region, can be replaced once every two years; Changhong KFR-25GW / H air conditioning on power no reaction (1) to observe the work of the indoor unit lights does not shine, with a multimeter to check the power outlet has 220V, the power supply is normal. (2) Remove the indoor unit housing Xuzhou Used wedding dresses, check the fuse on the indoor unit PCB, find the fuse has blown. In this case the insurance can not be immediately replaced with new reasons should be identified in order to be replaced. (3) further measurements with a multimeter ohm power transformer primary resistance, measured as 0Ω, blown fuse caused due to a short circuit. (4) carefully observe the transformer did not find traces of burnt, so suspect varistor damage, remove the varistors with a multimeter ohm measurement, cue really short-circuited. (5) Insurance tube put on the same model with the same parameters of varistors, the air conditioner is working properly. If not the same type varistor on hand, emergency method is temporarily not Varistor power test machine. Used air conditioning, Sheng Erda refrigeration, air-conditioning repair used in Xuzhou Xuzhou 圣尔达 by Refrigeration Electrical Services Limited. Xuzhou 圣尔达 Refrigeration Electrical Services Limited (xzktw.com) strong, credible, Xuzhou in Jiangsu Province of heat, refrigeration and air conditioning equipment industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead Sheng Erda refrigeration into the brilliant and you work for a better future!