Everything about refilling the air conditioner in a car with your own hands

Many car owners are interested in when to refill the air conditioning in their car? The answer to this question is quite simple. If there is still little freon – it’s time to refill the car air conditioner. To save extra money, you can do it yourself.

But how exactly do you refill the air conditioner yourself? What tools will be needed for this? And what rules should you remember? These issues will be discussed below.

The design and principle of operation of the air conditioner

The air conditioning system in a car consists of three parts - a compressor , a condenser and an evaporator (these parts are connected to each other using pipes).

Let's consider the principle of operation of the air conditioning system.

Inside the unit there is cooling freon in the form of gas. During operation, the compressor compresses the gas, which leads to an increase in the temperature of the freon mixture. The gas then enters the condenser, where it cools and turns into liquid. Cold freon passes through the pipes and enters the evaporator, where it evaporates - while the freon absorbs the heat surrounding it. This leads to a decrease in the temperature in the car and the conversion of the coolant into gas. At the end of the cycle, the freon is again supplied to the condenser and the process is repeated.

Working principle of a car cooler

It is impossible to properly service a car’s air conditioner without knowing its structure and operating principle. The climate control system includes the following elements and units:

external heat exchanger (condenser), installed next to the radiator of the engine cooling system;
internal heat exchanger (evaporator), mounted in the cabin air duct;
the fins of both heat exchangers are forcedly blown by fans;
the compressor, which creates the necessary freon pressure in the circuit, is driven by a belt drive from the crankshaft;
expansion valve, gas dryer;
connecting freon lines made of copper tubes.

Key moment! The operating principle of any air conditioner is based on the ability of the refrigerant to evaporate at sub-zero temperatures. At the moment of evaporation, freon quickly removes a large amount of heat from the air, significantly reducing its temperature.

To properly charge a car air conditioner, you need to imagine the operating cycle of the air conditioning system:

While in a liquid state, the refrigerant is supplied to the evaporator, through which a fan drives hot air. Freon evaporates, takes away heat from the flow and is sent further - to the compressor.
Inside the blower, the gas is compressed and moved to an external heat exchanger. The boiling point of a substance under pressure increases, so the freon in the external radiator condenses and releases the accumulated heat to the outside air.
After flowing through the dryer and expansion valve, the refrigerant pressure drops again. The gas again moves into the internal heat exchanger to evaporate and go through the cycle again.

When to refill your car air conditioner

Every year, for natural reasons, the amount of freon in the cooling system decreases by 10-20%, so it is necessary to periodically refill the air conditioner. Please note that the power of the device drops significantly even if the freon loss is 50 percent or more.

It is recommended to refill your car's air conditioner at least every 3 years!

Do-it-yourself refueling of a car air conditioner is required in the following cases:

Violation of the tightness of pipes;
Mechanical damage to pipes;
Condenser coated with rust.

How to check the quality of work

Insufficient air conditioning charging can lead to compressor failure, and the interior will not be sufficiently cooled. Excess freon will lead to automatic operation of the shutdown system and, therefore, also to a lack of interior cooling. So you need to refill the air conditioner only according to calculations.

You can determine the exact amount of refrigerant for a specific air conditioner in the instructions for the car or in tables published on the Internet

After refueling, you need to check the quality of the work done. This process cannot be called long: the car’s air conditioner is switched to active mode, and if cold air immediately enters the cabin, then the air conditioning system is charged correctly. The following will also help identify errors in refueling:

foreign odors from the deflectors (you may need to change the cabin filter);
freon leaks from air conditioner pipes (detected using a leak detector or visually);
extraneous noise (if present, corrosion of the compressor or condenser is likely).

In the event of a freon leak, you must seek the help of a repairman

Equipment and tools for refueling

To refill your car air conditioner with your own hands, you will need: a station for measuring pressure, an adapter with a tap, two hoses and a cylinder of freon.

From these components you need to assemble a device for refilling the air conditioning system.

Freon selection

To charge the air conditioner, use R134a cooling mixture .

Older installations ran on R12 freon, but in the nineties this mixture was banned due to its negative impact on the environment, and after the ban, the R134a mixture began to be used in air conditioners. To refill a car air conditioner, about 700-1000 g of mixture is required.

How often do you need refueling?

Freon is used as a refrigerant in a car's air conditioning system. During operation, involuntary leakage occurs, which cannot be stopped. During the year, the loss of freon is 15%, this is considered normal. To restore the required amount of refrigerant, the air conditioner should be refilled after three years. If the equipment is not new, then the system has to be refilled often. The charging technology for all air conditioners is the same.

If there is a large loss of freon, then it is necessary to make a diagnosis. Often the cause of leaks is a violation of the tightness of the connections. Special equipment is often used to diagnose the air conditioning system and detect refrigerant leaks.

Special equipment for leak detection

One such device is a leak detector. The sensitivity of modern devices allows for diagnostics and determination of the exact location of the leak.

When there is no equipment to diagnose the system, you can use another method: add ultraviolet dye when refueling. To diagnose leaks, you need to turn on the system several times after fully filling it with dye, and then check for leaks using an ultraviolet lamp. In places of leakage, yellow-green streaks will be visible.

Preparing for refueling

First of all, before refueling the air conditioner in the car with your own hands, you need to find and eliminate leaks, as well as perform vacuuming.

If the leaks are small, you can fix them yourself; for larger damages, we recommend contacting a car service center.

Finding and fixing leaks

If the freon in the air conditioner runs out due to damage to the pipes, then in this case you need to find and fix the leak. To find leaks, it is recommended to use a special tool called a leak detector . If there is no such device, then find the leak location as follows:

Make a liquid mixture based on oil and freon;
Add a special ultraviolet dye to the mixture;
Refuel and turn on the air conditioner;
After 5-10 minutes, take an ultraviolet lamp and shine it on the air conditioner - the damaged areas should turn greenish-yellow.

To eliminate a leak:

Take a metal pipe and cover the leak with it;
Place 1 clamp on both sides of the pipe;
Degrease the place where the clamps are attached (for example, with alcohol);
Secure the coupling parts with electrical tape.
Apply glue to the coupling, place the coupling on the pipe and tighten the clamps.

Pressure test

After eliminating leaks, it is necessary to check the integrity of the system. To do this, you should fill the air conditioner yourself with some safe gas (for example, nitrogen).

After refueling, be sure to measure the pressure - if after 30 minutes the pressure has not changed, this means that the system is completely sealed. Otherwise, repair any remaining leaks and repeat the test procedure.

Evacuation of the air conditioner

Now you need to evacuate the device to remove air and moisture droplets from the system. For evacuation you will need a special vacuum pump, and the procedure itself is as follows :

Turn on the heating system and warm up the car (if this is not done, then a lot of moisture will remain in the evaporator);
Take the vacuum pump and connect it to the car air conditioner - to do this, attach the pump pipe to the pipe;
Turn on the pump for 10-15 minutes. After this, close the valve and turn off the pump. Repeat the procedure 2-3 times;
Finally, turn off the pump and wait 2-3 hours for the temperature and pressure to normalize. After this, you can proceed directly to refueling.

Signs of freon deficiency

Since the gas pressure in the circuit can reach 20–25 Bar, a natural refrigerant leak of up to 10% is allowed on a used car. If the losses exceed the specified value, the cooling efficiency decreases noticeably - the air conditioner drives warm air.

When faced with a similar problem, arm yourself with the operating instructions for the machine, find the location of the heat exchangers, supply pipes and make sure that secondary signs of gas leakage appear:

traces or drops of oil at pipeline joints;
freezing of one or both highways;
one of the heat exchangers (usually the evaporator) is covered with frost;
Using a thermometer, measure the air temperature at the outlet of the deflector - it should correspond to the cooler setting.

Reference. Freon contains synthetic or mineral oil to lubricate the compressor. Therefore, at leaky joints, traces of the lubricant component appear first.

Before filling the air conditioner with freon, be sure to identify and repair the leak. Tighten the union nuts with a wrench and check the system for leaks using the only method available in the garage - vacuuming. Read more about this operation below.

Air conditioner refilling steps

Let's now find out how to refuel .

Please note that air conditioners differ very little from each other in their structure, so this scheme is suitable for all models:

Locate the low pressure line (it looks like a small wide pipe with a narrower pipe underneath) and open the protective cap.
Place the hose from the assembled filling device onto the nozzle.
Start the engine (speed should be about 1,300-1,700 rpm). Please note that the engine must be turned on during the entire refueling procedure, so it is recommended to place a hard object under the gas pedal.
Start air recirculation.
Turn the freon bottle upside down. After this, gradually open the main tap and the freon valve (this must be done simultaneously). Freon pumping will begin.
Watch the pressure gauge reading. The pressure level in the system should not exceed 275 kPa (otherwise you may damage the compressor).
When the hose near the nozzle becomes very cold and cold air appears in the cabin (about 6-10 degrees), you need to gradually turn off the engine and remove the filling device. The refueling procedure is completed.

How much does it cost to refill a car air conditioner?

If there is not enough freon in the system and the air conditioner does not cool the interior well, then there are 2 options: refill it yourself or contact a service station. If you go to a car service center, they charge an average of 1,500 rubles for a full refill of a car air conditioner. Some drivers do not fully charge the system, but simply add freon. This costs on average 300 rubles per 100 grams. Specialists measure how much freon is missing in the system and add it until the required pressure is reached. That is, if the system does not have enough freon 150 grams, then refilling will cost only 450 rubles.

At some service stations the prices are lower, at others – higher. However, everyone decides for themselves where to refill the car air conditioner. But this can be done at many service stations.

Air conditioner care

Now you know how to charge the air conditioner in a car with your own hands. In conclusion, let's talk about the rules of care :

Wash the radiator at least once every 3 months, as dirt and dust constantly settle on it, which significantly reduces the efficiency of the device.
In winter, you need to warm up the air conditioner at least once a month. To warm up, you need to drive the car into a warm place and turn on the cooling device for 15-30 minutes.

If leaks occur, contact a service center for repairs or repair the pipes yourself.

Watch the video yourself to see how to recharge the air conditioner in your car.

Preventive measures

Long-term operation of the car air conditioner without problems or leaks indicates that the car owner carefully monitors the operation of his vehicle and all its systems. There are literally two useful recommendations for self-service of an air conditioner, which are aimed at increasing the service life of the system and maintaining its efficient operation. Car owners need:

Periodically clean the radiator of your car air conditioner. The procedure for washing this element is not the most complicated, so there is no need to involve specialists in it.
Use air conditioning in winter. In winter, there is no need to cool the interior. Here the entire emphasis is on heating. But to prevent the air conditioner from breaking down prematurely, it should be turned on in winter. To do this, it is recommended to go into any warm room at least once a month and turn on the interior cooling at medium speed for 10 - 20 minutes.

When there are no breakdowns or leaks in the car air conditioning system, refilling freon yourself is not so difficult. You can easily cope with the task yourself. But in order to carry out all operations correctly, you should study the design of the air conditioner in advance, understand the principle of its operation, select the appropriate refrigerant and acquire the necessary equipment.

Why do you need to recharge your air conditioner?

A complete recharge of the climate system occurs if:

It is necessary to cleanse the system of bacteria and decay products. In this case, the old freon is removed, all components are cleaned and the air conditioner is refilled with liquefied gas.
Recovering the optimal amount of refrigerant. To begin with, all the gas is vented, a vacuum atmosphere is created, and then refilled to the required level.

How to refill a car air conditioner

The following brands of refrigerants are often used:

R-22. It has proven itself to be a reliable media, has high cooling efficiency and is cheap.
R-410A. Uses more pressure, improving performance, which saves energy.
R-134 a. It is safe for nature and does not harm the ozone layer, but has one drawback - high cost.

Any freon will be safe for health if refilling is done correctly. Photo: greenreport.it

Refueling instructions

Regardless of what kind of car you have and what the air conditioning system looks like, general instructions can be used for all cases. Although the systems look and work differently, they are united by the principle of operation and design. Therefore, it is not necessary to look for a manual for servicing the air conditioner of a specific car. If you decide to charge your air conditioner yourself, try not to deviate from these recommendations and strictly follow the instructions.

Remove all contaminants on the protective cap and the adjacent area of the low pressure line. Only after this can you safely open it without fear of debris entering the system.
Assemble the equipment and attach the hose to the filler fitting. If the refrigerant bottle comes with instructions for its use, be sure to follow the manufacturer's recommendations. Freon is supplied in different cylinders, so they may differ slightly from each other.
When refueling car air conditioners, you should start the engine and keep the speed at 1500 units. RPM support is required to pump freon through all lines of the air conditioning unit. Here it is better to use the help of another person, or use something to fix the gas pedal in the desired position so that the speed does not fall or rise.
Now you can turn on air recirculation using the appropriate buttons or controls on your air conditioner. The equipment is turned on at maximum values.
Open the low pressure line tap. In this case, the freon cylinder itself turns upside down. The canister valve gradually opens. At the same time, the engine continues to run, and the escaping refrigerant begins to charge the system.
While the freon leaves the cylinder and enters the air conditioner, you need to simultaneously monitor the pressure gauge readings. Make sure that the value in the low pressure line does not exceed 285 kPa. Optimally it should be at a level of 275 kPa. If you exceed the specified numbers, then this will lead to compressor failure.
To check that the system is properly charged, look at the filter drier window. If there are no bubbles and you can clearly see the transparent liquid, everything is working out correctly.
When cold air appears in the cabin (its temperature will be from 5 to 8 degrees Celsius), and the hose near the low pressure fitting becomes cold, like ice, the process can be completed. Close the cylinder and disconnect all contacts.

If you do everything correctly and according to the instructions, you won’t see anything complicated in refilling your car air conditioner yourself. Therefore, rely on the manuals, carefully read the recommendations of the freon manufacturer, and also do not forget about safety standards. If problems arise, when something does not work out and gets out of control, it is better to stop the work and send the car to specialists.

Let's sum it up

It is unacceptable to use a car equipped with air conditioning without using this wonderful device. It is necessary that the climate system works flawlessly and pleases the driver and passengers of the car with ease of control, excellent interior cooling parameters and other features. The comfort of traveling in a modern car, especially over long distances, is often determined by whether the car has air conditioning. If it doesn’t work, then the comfort will be conditional. You will have to open the windows, put your health at risk and listen to the rather strong howl of the wind.

Sometimes restoring or repairing an air conditioner is very simple, and you can do it yourself. You just need to study a little the theory of how the system works, and also buy inexpensive equipment that can be used in the future for regular maintenance. As a rule, such equipment will pay for itself after 2-3 uses, and you will be able to independently solve any problems associated with your car air conditioner at any time. But if you do not have experience and skills, you should entrust this procedure to specialists.

Recommended refrigerants

Before you start filling, you need to select the manufacturer of the freon to be filled into the car air conditioner.

The best option would be the following brands of refrigerant:

"XADO";
EcoFrost;
Refco;
Refrigerant;
Fotech International.

These manufacturers have been present on the domestic market for a long time and have rightfully earned a reputation as manufacturers of high-quality and reliable freon.

You can purchase the required refrigerant in specialized stores or online. The quality of these manufacturers is approximately the same, so you should pay attention not to the brand, but to your own financial capabilities.