How to Drain Car AC System?

Open the hood and locate the compressor.

Locate the reservoir tank and remove it from the car by unscrewing the bolts that hold it in place.

If you cannot find a reservoir tank, use a funnel to drain the liquid into a bucket or container inside your car.

Unscrew both of the lines from the compressor using pliers and attach them to a drain pan or bucket inside your car.

Wait for all of the liquid to enter into your bucket or pan before closing up everything again and starting up your engine.

Drain the system

1. Park your car in a safe place where there are no other cars around.

2. Put the car in park and turn off the engine.

3. Open up the hood of your car and locate the AC drain plug. It will be on the bottom side of your car, near the front tire.

4. Use an adjustable wrench to loosen the drain plug until it comes out completely.

Then, use a bucket or some other container with a lid on it to catch all of the draining liquid that comes out of your AC system.

You’ll need to empty this container periodically while you’re draining your system so that it doesn’t overflow before you’re done!

Remove the dryer

To drain your AC system, you need to remove the dryer.

1. Remove the dryer from the compressor, which will allow you to empty it.

2. Also remove the compressor from the engine, then remove the lines that connect it to your AC system.

Check the oil level

If the car has low oil, it can cause the air conditioning system to fail.

The car’s engine uses oil to lubricate moving parts, so if there is not enough oil, the air conditioning system will not work properly.

Make sure you check your car’s oil regularly so that you will know if it needs to be changed or topped off.

Check for leaks

The best way to do this is to start at the compressor and work your way up.

If you’re looking at an air conditioning system, then you want to start at the compressor and work your way up through the condenser, evaporator, expansion valve, and receiver/dryer. Take a look at each part for any signs of leakage.

If there are any signs of leakage, then you’ll need to replace those parts before your AC can be fully functional again.

Find the drain plug

The most important step in draining your car’s AC system is locating the drain plug. It will be located on the lower half of your vehicle and can be accessed by popping off the plastic cover and removing the nut underneath.

Check the transmission fluid level

To ensure that your car’s transmission fluid is at the proper level, you should check it every month or two.

First, make sure the engine is cool before checking the fluid level.

Then, open the hood and locate the transmission dipstick. Pull out the dipstick and wipe it clean with a paper towel.

Insert it all the way into the transmission until it stops, then remove it and check its reading against your owner’s manual’s recommendations.

If you need to add more fluid to bring it up to normal levels, pour it slowly into the dipstick tube until full, then replace everything as detailed in your owner’s manual.

Close the drain valve at the bottom of your radiator

To drain the ac system in your car, you’ll first need to close the drain valve at the bottom of your radiator.

Then, remove the radiator cap and allow the water to drain out into a bucket.

If you’re not sure where your drain valve is, consult your owner’s manual or ask a mechanic for assistance.

Once all of the water has drained from your system, you can refill it with fresh water and restart your car.


If you’re looking to drain your AC system, it’s important to remember that you should not do so unless it is completely necessary.

If you want to drain your AC system, start by turning off the car and opening up the hood. Next, use a funnel to pour three quarts of coolant into the radiator opening on top of your engine block.

After that, turn on the engine and open up all doors and windows in order to let hot air escape from inside. Once this has been done, start up your car again and let it run for about 15 minutes before shutting it down once more.

Repeat this process until there are no more bubbles coming out of your radiator or until you have emptied one gallon of coolant into your system.

Never open up a radiator cap while the engine is running or when pressure is still inside; doing so could cause serious injury or death.

Steven Hatman
Steven Hatman

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