What is the normal pressure for an automotive Freon gauge?
2 Answers
The low pressure for automotive air conditioning refrigerant charging is 1.5 to 2.5 kg, and the high pressure is 13.5 to 15.5 kg. Below is relevant information about Freon: 1. Introduction: Freon, also known as Fluorine, originates from the English word Freon, which is a registered refrigerant trademark of DuPont in the United States. In China, there is a divergence in the definition of Freon, generally defined as the collective term for halogen derivatives of saturated hydrocarbons (mainly methane, ethane, and propane). According to this definition, Freon can be divided into four categories: CFC, HCFC, HFC, etc. Some scholars define Freon as CFC refrigerant. 2. Main Uses: Freon is widely used as a refrigerant, foaming agent, and cleaning agent, extensively applied in household appliances, foam plastics, daily chemicals, automotive, firefighting equipment, and other fields.
The normal pressure of Freon in car air conditioning is crucial. Generally, at an ambient temperature around 80°F, the low-pressure side should be between 30 to 40 PSI, and the high-pressure side between 180 to 220 PSI. However, these values are not fixed; as temperature changes, so does the pressure. For example, on a hot day, the high pressure might rise above 250, which is fine as long as the cooling effect remains good. I've measured the pressure multiple times with a gauge and found that pressures below 20 or above 260 might indicate issues, such as refrigerant leaks or system blockages, which can affect the compressor's lifespan. It's also important to distinguish between refrigerant types. Older models might use R12, while newer ones mostly use R134a or the newer R1234yf—never mix them. I make it a habit to check the pressure during seasonal changes to avoid costly major repairs. If readings are abnormal, first check if the fan or condenser is clean before considering adding refrigerant.
