Last updated on January 25th, 2024
When you fail to vacuum your car’s AC system after servicing or installation, the system will run at minimal performance.
The reason is that the AC system is usually exposed to humidity, air, and moisture that accumulates in it and could cause serious problems if not checked early enough.
It doesn’t matter whether or not you have a pump. Here’s a complete guide on how to vacuum a car AC system without a pump. Just read through it, and you’re good to go!
Why Should I Vacuum a Car AC System?
The AC system of a car allows for the cooling down of the air inside the car when the weather is warm, thereby creating a more conducive temperature for both the driver and passenger(s).
Thus, vacuuming the AC system of your car is essential, so the dust, air, and moisture that builds up in the system won’t cause any damage.
During cold weather, the water inside the AC system freezes and could spark problems in the car. Plus, any water articles clogged inside the system can cause corrosion.
Additionally, not cleaning your AC system poses health hazards since the humidity and moisture trapped inside the system create a breeding ground for fungal spores, mold, and bacteria.
When the system is turned on, the spores are blown directly to your face, and you’ll be inhaling the contaminated air.
Knowing how to vacuum the AC system of your vehicle by yourself will save you time and a few bucks since you’ll not need to go to an expert anytime your car vacuuming needs to be done.
You can do the vacuuming with or without a vacuum pump. In addition, maintaining your car AC system regularly is very important.
Vacuuming is part of the maintenance schedule. It protects and conserves your AC system from damage caused by elements like moisture, debris, and more.
How to Vacuum Car AC System Without Pump
Air conditioning systems are built to function only with oil and refrigerant, not debris, moisture, or air.
Even though a vacuum pump is the best option for AC vacuuming, it’s not the only available solution.
Alternatively, you’ll need to install access valves on low and high-pressure sides to vacuum your AC system properly.
Below are steps on how to vacuum a car AC system without a pump:
Depress the Access Valve
While paying particular attention to the pressure on the lower side of the valve, turn on your compressor when the high and low-pressure valves are in place.
Then, depress the pressure on the higher side of the access valve.
Immediately the high-pressure side reaches its lowest point, close it and turn off your compressor. This process will take just about 5 minutes.
Charge the low-pressure side
After depressing the access valve, charge the pressure of the lower side to about 14 psi.
At this point, you must carefully observe the high and low-pressure sides for up to 3 minutes and turn on the compressor again. The observation is to ensure that the two sides are on equal readings.
Disconnect the high-pressure side of the access valve
Similar to what you did in the first step, depress (disconnect) the high-pressure side of the access valve again.
But, here, all you have to do is monitor the pressure on the low side instead of the high side pressure.
Once it reaches its lowest point, allow the high-side pressure to close on its own. After the valve closes completely, turn off the compressor.
Repeat the 2nd and 3rd Steps
Akin to what you did in step 2, charge the low-pressure side to about 14 psi. Then, pause and observe the pressure on the different sides of the access valve for about 3 minutes until they equalize.
Go ahead, turn your compressor on, and depress the high-pressure side of the valve again.
To confirm whether your evacuation process is successful, check if the low-pressure side goes lower than in the previous steps. If it doesn’t, then you’re getting it right.
Plus, it shows the gradual release and absorption of the refrigerant in the oil.
Additionally, if the high side pressure isn’t releasing gas, allow it to go off. That way, your car’s AC system will be void of any moisture or debris previously trapped.
Charge With Refrigerant
Ensure you charge your vehicle’s AC system with the recommended amount of refrigerant. Then, turn off the compressor, and your system is in perfect condition.
However, there may be little variations in the process depending on your car’s AC system type.
Problems From Not Vacuuming a Car AC System
There are possible issues that arise from not vacuuming your car’s AC system. They include:
Increased System Pressure and Temperature
Reduced condenser capacity results from less refrigerant, which leads to an increase in the temperature and pressure of the AC system.
Reduced Condenser Capacity
The air in the AC system occupies more space than the refrigerants because it’s a non-condensate gas, thereby reducing the AC’s cooling capability and condenser.
Acid formation occurs when the lubricant of the AC integrates with moisture. This integration can lead to subsequent failure in the AC system’s internal mechanisms and the formation of rust.
Reduced Refrigerant Charge
The refrigerant takes less space than the non-condensate air. When the refrigerant is less, the amount to be charged in the refrigerant system (refrigerant pipe) will be less.
Increased Energy Consumption
The power load of the compressor increases when it overheats. This increase requires more energy to function properly, which will likely cause the energy bills to increase at month-end.
What Will Happen if I Don’t Vacuum My Car AC System?
You’ll be putting your vehicle at risk of mechanical parts failure if you don’t vacuum it when it’s supposed to be vacuumed. Also, there’s a high possibility of reduced refrigerant charge, acid build-up, and an increase in energy consumption.
Does Vacuuming your Car AC System Eliminate Oil?
Vacuuming doesn’t remove oil from the AC system. So, there’s no need to worry about replacing the PAG gasoline. The only time you’ll need to inject oil is when the compressor or accumulator is disconnected.
How Often Should I Vacuum My AC System?
The recommended period for servicing the car Ac system is once a year. Spring happens to be the right time to do the servicing. It’s not out of place to carry out the maintenance on your own, but if you notice any major issues, contact a professional.
What Will Happen if I Overcharge My AC?
Using excess refrigerant or overcharging the AC system causes compressor damage. Some of the signs of excess refrigerant include high condenser pressure, natural overheating, overcooling, and rapid temperature discharge.
The excess refrigerant clogs the compressor and causes the AC’s temperature to reduce below average. In some cases, it could flood the compressor, leading to the failure of the mechanical parts.
Why Do I Have to Vacuum the AC System in My Car?
You should consider installing evacuation equipment in your vehicle to avoid issues caused by moisture or air in the air conditioning system. Additionally, you can evacuate the moisture or air in the car’s AC system before charging the refrigerant.
Vacuuming a Car AC system is one of the most recommended and beneficial maintenance schedules. Don’t forget to carefully follow the steps highlighted above.
By the way, you’re free to feel proud if you successfully vacuum the system. Besides, you’ll be saving money and time if you can do the vacuuming yourself.
The only time you may need a professional mechanic is when the system begins to develop major problems.