What is the pressure of 134a?
1 Answers
Automotive air conditioning 134a pressure standards: The normal high pressure should be 1.3-1.7MPa or 13-17kg/cm2, and the normal low pressure should be between 0.15-0.25MPa or 1.5-2.5kg/cm2. In summer under direct sunlight, the high pressure may be slightly higher, up to about 2.5-2.8MPa, but generally does not exceed 3.1MPa. Automotive air conditioning refrigerant, commonly referred to as Freon, is also known as "refrigerant" or "coolant" in the market, and is divided into environmentally friendly (R134a) and non-environmentally friendly (F12). R134a is the most widely used medium-low temperature environmentally friendly refrigerant. It has excellent comprehensive performance, making it a very effective and safe alternative to dichlorodifluoromethane (CFC-12), and can be applied in most areas where CFC-12 is used. To measure the high and low pressure of the automotive air conditioning system, the engine should be idling, and the measurement should be taken at an ambient temperature of 35 degrees Celsius. If the low pressure is higher or lower than this range, it indicates abnormal expansion valve regulation. When the engine throttle is increased, the measured low pressure should decrease with the engine speed. The faster the speed, the faster the pressure drops, indicating good compressor performance. Otherwise, it indicates a compressor fault. The outermost ring of the low-pressure gauge shows the MPa value. For example, if the pointer points to "3," the current pressure is 0.3MPa. The second ring from the outside to the inside on the low-pressure gauge shows the value in kg/cm2. The innermost ring of the high-pressure gauge shows the bar value in red. For example, if the pointer points to "20," the current pressure is 20bar. The conversion formula for different pressure units is: 1MPa ≈ 101kg/cm2 ≈ 10bar ≈ 145Psi.