What are the reasons for the increase in car air conditioning pressure?
3 Answers
The reasons for the increase in car air conditioning pressure are: 1. There is air in the air conditioning system; 2. The expansion valve is blocked or malfunctioning; 3. Excessive refrigerant; 4. Poor heat dissipation of the condenser; 5. Frosting of the low-pressure pipe; 6. Cooling fan failure; 7. Engine overheating; 8. Insufficient refrigeration oil. The solutions for the increase in car air conditioning pressure are: 1. Evacuate the air from the system; 2. Replace the expansion valve; 3. Refill refrigerant quantitatively; 4. Clean the dirt from the condenser and radiator grille; 5. Refill refrigeration oil. The functions of car air conditioning: 1. Adjust the temperature inside the car; 2. Kill bacteria and remove odors inside the car; 3. Purify the air inside the car.
After driving for so many years, what I fear the most in summer is the sudden rise in car air conditioning pressure. The reasons are usually overcharging the refrigerant or dirt clogging the pipes in the system. I remember once when my old car's AC wasn't cooling well, I thought it was low on refrigerant. But after topping it up, the pressure skyrocketed. A check revealed the fan was broken, causing poor heat dissipation. On hot days, the engine gets scorching, and with the front condenser clogged with dust and no ventilation, the cold air gets trapped. Ignoring this could lead to the refrigerant pipes bursting, costing at least a few hundred bucks to fix. Now, I've made it a habit to check the AC system before summer every year, especially cleaning the front grille and fan to ensure smooth airflow and avoid repeating past mistakes. I also keep an ear out for any unusual AC noises while driving—if I hear anything odd, I pull over immediately to let it cool down. Safety first.
With nearly 20 years of auto repair experience, I find rising AC pressure a real headache. The three most common scenarios are: 1) Overcharged refrigerant—novice drivers often think more is better, but excess causes pressure surges that can burst pipes; 2) Air or moisture intrusion—excess humidity cripples condensation and clogs lines; 3) Worn fans or compressors—poor operation traps heat. I've even seen stuck expansion valves causing refrigerant backflow buildup. Always wear protective gloves, use gauges to test, and immediately vent excess refrigerant if detected. Never skip routine maintenance—clean radiator filters regularly and keep the engine bay clear of debris during operation. Remember, excessive pressure wastes fuel and risks damaging the entire AC system—get professional calibration early.
