Before You Start

Before you start recharging your vehicles air conditioner system, you want to check to see which refrigerant your car uses. Some automobiles use the newer R134. Other vehicles may still use the R12 refrigerant. If you plan on recharging you air conditioner yourself, you should always check the owner's manual for your vehicle to see which refrigerant your car uses. You can also check your repair manual for this information as well.

If your vehicle was manufactured in the late 1990's then there is a good chance your vehicle takes the R134 refrigerant. If your vehicle happens to use the older refrigerant, the R12, then you should visit your auto repair shop and have it converted to the newer refrigerant. You'll be glad you did.

If your AC system is already R134 equipped, follow the steps below to recharge your air conditioner so you can keep cool on those hot summer days.

The Air Conditioning Recharge Kit

These kits usually contain a can of R134 and a pressure gauge - all in one. They do a good job with this particular do it yourself procedure. Even if you have limited or no experience with maintaining an air conditioning system, these all in one kits are simple and easy to understand. Some kits have a clearly visible pressure gauge right on the cap, but any all in one type kit will do.

Preparing your All in One Recharge Kit

Unpack your all in one kit. Locate the can of can of refrigerant, a rubber hose and the pressure gauge. Just follow the instructions enclosed in your all in one recharge kit package and assemble the pressure gauge. Usually, the flexible hose enclosed will already be attached to the gauge.

Before screwing the gauge to your can of R 134 refrigerant, make sure you turn the gauge counter-clockwise gradually until it stops. You'll find a pin in the assembly that you will use to pierce through the can of refrigerant once everything has been put together tightly.

When you're ready, control the pin by turning your gauge clockwise until the pin pierces through the can. Remember you don't want to pierce the can until you're ready, so make the pin is all the way out before the kit is completely assembled.

Assembling Your All in One Recharge Kit

Making sure the pin is complete out, go ahead and assemble the pressure gauge and the rest of the kit. Screw that flexible rubber hose to the pressure gauge tightly. Don't tighten the whole thing to the top of the can just yet. We will need to check reading first.

Before taking an accurate reading, you will need to calibrate the gauge. On the face of the gauge, you'll find indications of different temperatures. Simply turn the calibration dial to match the outside temperature. If it happens to be a nice day, say 70 degrees outside, make sure you calibrate the temperature on the gauge to reflect the same.

Locate the Low Pressure Port

Your air conditioning system has a low pressure and a high-pressure side. You want to recharge your air conditioner system through the low-pressure port side. Stop and consult your owner's manual just in case. Your automobile will also have a cap over the high and low-pressure ports. One cap should be labeled "H" for the high-pressure port and the other will be labeled "L" for the low-pressure port. The ports are different sizes so there is no way you attach the pressure gauge or hose to the wrong port. It's a type of safety measure but it's always a good idea to check anyway.

Clean the Low Pressure Port

An automobile's air conditioning system is delicate in some areas. If any dirt or debris gets inside the compressor, it may cause your air conditioning system to fail leading to expensive repair. As a safety precaution, clean the outside area of the low-pressure port before removing the cap. Repeat this step after the cap is removed also. This may seem unnecessary but it doesn't take much to destroy the system if so much as one tiny piece of debris finds it way into your vehicles compressor.

Attaching the Hose and Testing the Pressure

STOP: Before attaching the hose, you must turn the gauge clockwise until it tightens. This seals the gauge so you can attach it to the AC port safely.

With the low-pressure port cleaned, you can now attach the rubber hose that connects your vehicle to the pressure gauge. This does not screw on, but rather uses latching mechanism.

To attach the hose to your low-pressure port first pull the outside of the fitting back and slide it over your low-pressure port; then release it. Start the engine and turn your air conditioning up to the high setting. Look at your gauge and see how much pressure is building up in your air conditioning system. You will need to give the system a few minutes so that the pressure can rise and equalize. Once this happens you can take accurate readings to see whether you need to recharge the air conditioning system.

Preparing to Add Refrigerant

After taking a reading, you may find that more R134 refrigerant is needed to raise the pressure in your air conditioning system. If so, follow these steps.

1. Remove the flexible hose from the port. 2. Turn your gauge counter-clockwise again and pull out the pin. 3. Now, tightly screw the pressure gauge assembly onto the can of refrigerant. 4. Pierce the can. Turn the gauge clockwise all the way, and you should hear the sound of the pressurized being pierced.

Add Refrigerant (R134) to Your System

Now that the can is pierced, you can re-attach the rubber hose to your low-pressure port on the air conditioner line. Start your car's engine and turn the air conditioning to the high setting. You need to give the air conditioning system a moment for the pressure to rise.

Once it has risen, turn the gauge counter-clockwise to start releasing the refrigerant into the air conditioning system. While the refrigerant is being added, observe the pressure gauge carefully. The part of the gauge that is calibrated to the temperature outside will indicate when the air conditioning system is full. Consult your all-in-one recharge kit for even more instructions. A nice tip is to rotate the can of refrigerant back and forth slowly while you waiting for the pressure to rise. This will help to distribute it as it comes out.

Last Step

You want the right amount of refrigerant in your system. Make sure your watching the gauge as the refrigerant is being distributed to be sure. If you're off by a small amount, say a few pounds, don't worry. If you take the time to fill the refrigerant to the appropriate levels, your air-conditioning system will run cool again.

When you've finished filling your refrigerant, remember to put the cap back on the low-pressure port. This will keep the dirt out. Once you're done, hold onto your pressure gauge. Even if you wind up using the entire can of refrigerant you'll want to hold on to this because you can always re-use it to check your air conditioner system the next time. All you need is a new can - and not the whole kit!

Bond Mejeh produces automotive related articles for Quick Cash Auto, a service helping people sell a car. Quick Cash Auto not only buys pre-owned vehicles of any make or model, but they also provide numerous articles about vehicle repair and automotive news.

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How to Recharge Your A-C - Recharging Your A-C
By Bond Mejeh
In order to recharge the air conditioner's system, you'll need a pressurized refrigerant, or Freon, and a pressure gauge to observe how much Freon in the system. You can spend quite a bit on air conditioning recharging tools. Most of them are purchased by auto repair professionals. If you happen to have several automobiles, then it might make sense; it could really be worth the investment. However, if you only own a car or two, you might do better with an all-in-one kit.