How Much Vacuum to Pull on Auto Ac System

Find How Much Vacuum to Pull on Auto Ac System

It’s important to find out how much vacuum to pull on auto ac system. Improper combination of vacuum inside the vacuum system can hamper the engine and the ac system as well. So, it’s better you know exactly how long to pull the vacuum from the system.

However, for a fact know that, it has utmost importance of pulling vacuum out from an auto or any ac system. Over the time, many dirt and debris might have accumulated. Also, the air and moisture can also get there up to a major amount. So, it’s necessary to pull vacuum for an ac system.

So, next, we’ll talk some primary or initial things on pulling vacuum on auto ac system.

Primary Talks on Vacuum to Pull on Auto Ac System

In general, the ac system recharging is basically the fueling of refrigerant to charge the entire system. Furthermore, along with this, the vacuuming down the system is done from a primary level. But, when we recharge the system? Well, once you’ve done the repairing, it’s time to fuel the system with refrigerants. There’re many type refrigerants in the industry.

Types of Refrigerants in Auto Ac System

  • R-12 is an old type of refrigerant. It was in use before 1995. Basically, no one uses it nowadays.
  • R-134a: It’s an upgraded version of R-12 and it has more molecules added to it. The extra molecules help the refrigerant to have more environment friendly option.
  • 1234yf: It’s the refrigerant we use nowadays. It’s more environment friendly. But, there’s a catch here. This one is flammable and comes with more expense. German based car industry still use the R-134a for the flammable feature of the 123yf refrigerant.

Why You Require Vacuuming for an Auto Ac System

Let’s understand the importance of vacuuming or pulling vacuuming on an auto ac system. For obvious reasons, you ac needs maintenance. The presence of extra air can hamper its performance and other equipment around an AC system. So, the need of vacuuming for an auto ac system arises.

Moisture is another factor that isn’t good for an Auto Ac system. The combination of air and moisture with oil can damage the ac and more components of a vehicle. To remove the moisture, vacuuming is the best option you can have.

On the other hand, the compressor needs maintenance as well. But, if you vacuum down the auto ac system, the compressor maintenance is automatically done.

The Steps to Pull Vacuum on Auto Ac System

Now, let’s learn how to pull vacuum and how long to do that.

Locate High and Low Service Ports

Finding or locating the high and low service ports is necessary. And, it’s a must to have the engine off before you do it. Wearing safety material like eyewear, gloves, and other is necessary. Place the high port in between the condenser and the valve ( expansion one).

On the other hand, to return the line of the firewall or evaporator and compressor, locate and connect the low service port. This should be the combination of high and low service ports.

Preparation of the Gauge Set

It’s the step without which you should not move further in vacuuming an auto ac system. The gauge set will basically let you connect the whole ac system to the pressure ports on both the low and high ides.

It’ll also give you the readings during vacuuming down the system and recharging the system. However, when you connect the gauge sets, the connections should be tight in order to avoid any leaks. By tight, we mean it’s air tight. The red gauge and the connector part is the high pressure side.

Connecting the Gauges

Okay, now, it’s time to connect the gauges. Connecting the gauge to the port is the task. To do that, it’s necessary to connect the low port to the return hose and the compressor. It’s done when you lift up the connector ring and push it downward.

The above process is to be followed for both low and high pressure ports. The red and blue colors are to avoid any confusion the high and low ports.

Gauge Readings

Gauge readings will give you the vacuuming reading. There’ll be readings on both the high and low pressure side. But, know that pressure will be near to zero all the time.

Connecting the Vacuum Pump and Start Vacuuming

Now, that there’s almost no pressure, it’s time to vacuuming the ac system. Do the vacuuming for 30 straight minutes. In this step, at first, connecting the hose on the center to the pump is to be done. Then, you can go ahead and turn the unit on.

Next, you should open the low side pressure port and start to pull the vacuum. You’ll find that the gauge needle will move into the vacuum gradually. In then next minutes, there’ll be air coming out of the system as the vacuuming is going on.

After 30 minutes, stop the vacuuming.

Disconnect the Gauge Set

Now that the vacuuming is over, you should go ahead and disconnect everything including the gauge set.

Keeping the set connected can let the air and moisture build again in the system shortly.

Final Thoughts

So, you can see that it takes only 30 minutes to vacuum an entire auto ac system. If the system holds up to 30 inches on the gauge readings, then, understand that it’s time to stop the vacuuming.

Always remember that the pressure readings on the gauges should be near to zero all the time. One last tip is that, always keep all the connections airtight for a smooth vacuuming process. Protection Status
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