高压正常,低压偏高,空调效果不好的原因分析（High pressure normal, low pressure high air conditioning result is not good reason analysis）.docVIP

高压正常,低压偏高,空调效果不好的原因分析（High pressure normal, low pressure high air conditioning result is not good reason analysis） Many of the cars used especially for a period of time of the vehicles are often high normal 14-15 kg (up only slightly not more than 17 kg), but low pressure is high (2.5 kg), then the air conditioning effect will become worse, and this phenomenon has plagued us, so many mechanic which is at a loss what to do. What causes, what good method can be solved? Any low pressure (higher than 2.5 kg) of the car, always accompanied by air-conditioning effect is not ideal. And determine the low-pressure pressure, if these reasons: 1): the greater the heat load of heat load, the temperature will increase the evaporation tank, evaporating pressure will rise. While the heat load is related to the environmental temperature, the hot days of environmental temperature is higher, the heat load is larger, the general low cost car in summer when there will be pressure evaporation (both low pressure) with the temperature rising, the evaporation temperature increased, outlet temperature starts to rise, the driver did not feel cool day when air conditioning effect is good, of course for senior automotive load design is large enough, the effect is very small. While the heat load is not the peoples will. 2) expansion valve opening: when the suction amount, expansion valve opening degree is large, low pressure is more high. The effect of air conditioning car is after all is the refrigeration quantity and size, air temperature and air volume / pipeline, with the evaporation temperature of refrigerant into the box / evaporation amount. The evaporation temperature is related to the evaporation pressure, when the compressor suction amount (and speed), the expansion valve opening is greater, more into the refrigerant evaporation tank, which vaporized refrigerant vapor such as compressor can not be sucked to produce certain pressure quickly, then the control is only in a large number o