How to Vacuum Car AC System Without Pump

You must vacuum your car AC system annually to eliminate excess moisture. Failure to do so means the system will start leaking, after which the gas in the refrigerant contaminates the surroundings, leading to stale air. That stale and contaminated air can likely cause allergies or respiratory diseases.

Fortunately, you don’t have to resign yourself to this fate. Even though you don’t have a vacuum pump, you can still vacuum your car’s AC system and get it spick and span. In this guide, we’ll delve into the right way of how to vacuum a car AC system without pump.

How to Vacuum Car AC System Without Pump

Here’s a step-by-step process of how to vacuum the air conditioning system of your car in the absence of a vacuum pump.

1. Deject the Access Valves of Your AC

For optimal functioning, you need to install access valves on the low and high sides of the AC compressor. The next course of action is to close the valve on the high side and set the AC compressor to a particular pressure on the low side. The pressure will rise and trigger the high side valve and compressor to close.

2. Power Up the Low Side of the Valve

In this step, you’ll need to alter the low-pressure side of the air conditioning system to 14 psi. Run the friction for a few minutes to adjust the pressure on the low and high sides of the compressor to equilibrium.

3. Eliminate Pressure from the High Side Valve

You can adjust the compressor behind the service valve by pushing it against the high valve to achieve the desired outcome. Close the compressor and high valve until the low-pressure side gets to the operating pressure.

4. Repeat the Second and Third Steps

For three minutes, continuously alter the machine’s pressure to 14 psi and equalize the pressure. Then, power up the compressor by dejecting the valve on the high-pressure side of the compressor.

If there’s no moisture, air or vapor expulsion through the high-maintenance valve during this process, it should remain closed. The vacuuming mechanism is nearly complete by the AC system, and no pump is required.

5. Charge With a Refrigerant

Lastly, pump the refrigerant into the AC unit. The quantity of refrigerant required is as outlined in the user manual. Once you’ve introduced the refrigerant into the AC system, that’s your cue to switch off the compressor.

The Importance of Cleaning Your Car AC

Cleaning the AC system entails sanitizing the evaporator inside and the air ducts. The liquid refrigerant alters its aggregate state from liquid to gas. The process requires energy in the form of heat from the air pulled by the air cooling system.

Although you may not realize it, the condensate drip pan at the back of your refrigerator serves as the perfect breeding ground for bacteria and fungi.

The evaporator absorbs heat from the air to evaporate the refrigerant and cool the incoming air. A considerable amount of condensed water in the evaporator is generated and drained through a hole. Besides bacteria, fungal spores grow in the evaporator and vents, causing a distinct musty odor emanating from the AC unit.

The most crucial thing is not only your health but that of your passengers. That’s because the ventilation system peppers fungal spores directly into the air that you and your passengers breathe.

Disinfecting the AC system is typically conducted as part of the maintenance, ideally every year. Moreover, you’re advised to replace the cabin air filter, typically referred to as the pollen filter, after every clean.

How to Recharge and Vacuum an Air Conditioner

Let’s explore the step-by-step process of how to conduct a quick refrigerant recharge of your car’s AC system.

  1. Until you start the car, park it on a flat surface when the engine is off. When it comes to emergency braking, wear safety gloves and goggles, then stop at the gearbox.
  2. Invest in a generic charging set that’s available at your local car dealer.
  3. Remember to remove the valve seat protection before starting the engine.
  4. Once you take off the dust protector, locate the low-pressure side port on the refrigerant.
  5. As you thrust the tube into the inlet port, hold the retaining ring. It’s worth keeping in mind that the low-pressure port is incompatible with the high-pressure counterpart. Resultantly, that curbs potential mishaps.
  6. Once you install the replacement kit, you’ll notice that the pressure gauge indicates the state of charge on the low-pressure side of the unit.
  7. Once you secure the kit, start the engine and activate the AC system to the highest level.
  8. Wait 30 seconds for the compressor to be up and running, after which you’ll notice a plummet in pressure.
  9. For the refrigerant to be a snug fit in the unit, press the plunger inward and release it. Doing so will cause a rise in the pressure gauge, implying the transfer of fluid from the can to the reservoir.
  10. Once the pressure gauge plummets again, the plunger will automatically be released.
  11. Repeat the process until the device pressure is accurate. Furthermore, avoid overfilling the canister.
  12. With a rise in pressure, monitor the temperature of the passenger cabin breather ports coupled with the evaporator outlet tube that might be cool to the touch.
  13. Once you switch off the ignition, shut off the pump and AC.

car ac

Bottom Line

Now that you know how to vacuum a car AC system without a pump, you and your passengers can inhale clean air that’s free of allergens and other contaminants that are detrimental to your health. Furthermore, you can keep the unit functioning optimally for an extended period without the need to rope in a specialist.

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