Diagnosis of car air conditioner

At automakers, the rule of equipping machines with air conditioners appeared back in 1933. However, the first copies equipped with them appeared only in 1939. These were Packard devices, and they were collected manually. It should be noted that these devices were not very reliable, they had high cost and low efficiency. In this case, the first climatic system took place under the hood in the car interior, and also half the volume of the trunk.

Everything is much better with these devices. They have become much more compact, their efficiency has increased significantly, as, indeed, reliability. But every now and again motorists face problems in their work. Let's see how the air conditioner is diagnosed in the car.

How is the car air conditioner

In climate automotive systems, this device is a single unit with ventilation and heating of the cabin. The principle of operation of this device is completely analogous to that of an ordinary refrigerator.

But the features of air conditioners in cars is that the power is not electricity, but a little power from the engine. So, energy is given from the crankshaft using a drive belt.

By design, the car air conditioner is a sealed system filled with refrigerant and oil, which lubricates the system and the compressor.

Principle of operation

When the driver starts the climate system, a special electromagnetic clutch pulls the pressure plate to the pulley. This pulley rotates continuously from the drive belt.

After that, the compressor starts, and the refrigerant starts flowing through the pipelines, until Freon hits the condenser. The condenser is designed to cool the heated refrigerant. This part is located near the radiator in the engine compartment - the electric radiator fan helps cool the freon. When the refrigerant cools sufficiently, it enters the receiver in the form of a liquid. The latter is used as a filter. It cleans condensate and removes dirt and particles from it, which are the consequence of wear. Then the liquid is sent to a special thermostatic valve.

This node is actually an automatic throttle. It delivers the condensate to the evaporator in a state of gas. The evaporator, through which practically ice-cold Freon passes, cools and cools down sufficiently. And thanks to the fan this cold can fall into the cabin. Next - the next circle and until the driver does not shut down the system.

How is the air conditioner diagnosed?

Before you look for malfunctions in the interior of the device, try as closely as possible to inspect the condition of external parts. This should be done to detect possible mechanical damage. If you did not find anything, it's still too early to rejoice. A popular breakdown is a leak. You need to find it.

How to detect a leak in the air conditioner

Several decades ago, such a diagnosis of the air conditioner for leaks was carried out using a special small gas burner. Here the whole point is that freon has a special property. When it is detected, the flame changes color to green.

It must be said that the method is not only not effective, but also quite dangerous. When this substance burns, a very dangerous poison is released - phosgene.

Arming

Today, leak detection is performed in two ways. So, there are special devices - electronic leak searchers. You can also use ultraviolet.

A leak detector is a special device that captures freon vapors in the air. The sensitivity of these devices is sufficient to detect leaks in an amount of 5 to 10 grams per year. The market offers a variety of different models of these devices. Most of them are quite simple in functionality and suitable for home use. With this device, diagnosing the car air conditioner with your own hands is much easier. Others are more intelligent. But the device does not give any guarantees that the leak will be detected immediately. This device can detect only a cloud of freon. It happens that you can think of one tube, but another one. Especially difficult is the diagnosis of the air conditioner, when the tubes are located almost next to each other. This can be helped only by the great experience of such studies. You can also use the exception method - all the handsets are removed and checked in turn.

Power of ultraviolet

But even with leak detectors, holes are not always detected. Very often it happens that freon decreases in a few months and only at certain pressures. Or, for example, places where leaks occur very often are very close to each other. The apparatus feels the proximity of the gas, but can not find a specific place.

Then you should take advantage of the opportunities that the ultraviolet gives us. This diagnosis of the car air conditioner helps to more accurately detect a harmful and elusive leak.

The essence of this method is the use of the dye. The system must be fully refilled, but along with Freon and oil, a special substance is added, which gives a bright glow in the ultraviolet rays. The dye will not affect the operation of the system in any way, there is nothing to be afraid of. Most manufacturers add dye to their systems still in production. It is very important that a full refueling is performed. The desire to save here should not be, otherwise all this diagnosis of the car air conditioner with its own hands loses its meaning. Also there is a risk of premature "death" of the device.

After refueling, you can drive, use the climate at full capacity. When you feel that the unit has become worse to work, then you need to put the car in the garage and enlighten all the pipes and mains with a special lamp. To get an accurate result, it is advisable to work in dark rooms. The places from which freon flows out are easy to see. They will glow with poisonous-yellow streaks or nebulae.

Advantages and disadvantages

But with all its merits, this method has its drawbacks. So, not all the tubes can be seen - this diagnosis of the air conditioner requires the dismantling of certain parts or areas of the system. Among the most hard-to-reach places is the evaporator, which is hidden away in the torpedo. So that you do not have to disassemble half the car, you can diagnose the drainage tube. If it does not, try using a leak detector.

If the system on the car has already been dismantled and disassembled, and the dye was filled in, then there is a risk that the diagnosis of the car air conditioner will not be accurate.

It even happens that from the first time you can and do not find anything. Electronics can not see anything, the dye is not visible to the eye, and the coolant flows away somewhere. If you have any doubts about this, it is better to use two methods in diagnostic procedures.

Test the compressor

The diagnosis of the car air conditioner also includes checking the operation of the compressor. During the test it is necessary to find out how efficiently the unit works. The malfunction of this node can be determined by the sound - during operation it unnaturally rustles.

There is another option for checking the compressor. Start the air conditioner, then, when the compressor starts to work, grasp one hand for the metal part on the return line. For effect, grasp the knot with the whole hand. In a couple of seconds, the hand will feel like the tube will literally freeze. All is well - it's if you feel like you took an icicle in your hands. Ideal work - if the cold reduces the bones of your brush. Here such diagnostics of the compressor of the conditioner will help to learn, this knot is broken or works.

In addition, it is also necessary to diagnose all the electrical components of air conditioning in the cabin. They are different couplings, sensors, fans.

How to check the tightness

This is a simple way, which is to find out if there is much freon in the system. To do this, just look in the so-called window. You can find it in the area of the dehumidifier. This window is not on all devices, but if it does, you can get all the information about the state. If the refrigerant has turned white and there are bubbles in it, then further, more complete diagnosis and filling of the air conditioner is required . If the refrigerant is in the correct state, it is transparent and has a uniform consistency.

Typical malfunctions of car air conditioners

Compressor and depressurization - this is not all that can happen with air conditioning in your car. Many of the failures can be detected independently.

For example, among other faults, a breakdown of the condenser or radiator is considered quite serious. If it really does not work, the salon will be hot air. The main causes of this annoying breakdown are mud. It is necessary to eliminate this malfunction, otherwise serious consequences will be expected in the future.

Evaporator also often fails. This happens because the part is corroded. The blame for everything is the same dirt that clogs the pipes through which the condensate can merge. Diagnosis of malfunction of the air conditioner in this case is based on the appearance of an odor in the cabin, low efficiency, water.

Also among typical faults are problems with the receiver and the thermostatic valve. These failures can lead to serious consequences. Try to pay more attention to your car. Then it will not disappoint you, and your ride will be comfortable and cool.