If the air conditioner started to make a noise is the first sign, since it suggests that the technique should be checked. Noise emitted by air conditioning, it is possible to determine the nature of the fault. Try to conduct a diagnosis yourself. Minor repair of air conditioning will cost a decent amount, but in fact simply replace the filter or clean the device from dirt. Check for a restriction if the outside unit of the air conditioner with dust or fluff, the pump may make noise due to dust and dirt. If external power is not available, you can tilt the front panel on the indoor unit and inspect the filter. Contamination of the compressor is the main cause of failure of air conditioners. If you are familiar with air conditioner, try replacing the filter yourself, if not call the repairman for service. If the filter is clean and the noise persists, check as spun bearing. It rests on a special pulley and bolted down. Qualitatively spun the bolts are not supposed to make noise - background noise can occur due to poor fixation. Another cause of noise could be a broken bearing, if you do not understand the technology, call repairmen, and specify from where came the noise.It so happens that turning on the air conditioning emits a short sound but will not start. Perhaps, to blame the trigger or low voltage, or has failed, the control system of the compressor. Repair of one Board is cheaper than repairing the entire compressor. Be sure to describe the nature of the noise to show the place whence came the noise – you will facilitate the diagnosis, and the wizard will quickly find the cause of the problem. Follow quality replacement parts. Note the similarity of the new and old parts. Not all of the wizard, set equivalent parts, and the Chinese "compatible" devices will affect the operation of the air conditioner is not the best.