Diagnostics of air conditioner with your hands
The air conditioner in a modern car is a usual thing and very desirable in hot season, but, as well as any system of the car, it can fail. Today we will talk about the diagnostics of air conditioner with our own hands, though I would like to warn you at once that not all failures of air conditioner can be diagnosed and eliminated in the conditions of garage – you may need special equipment, knowledge and skills. If you can’t find out the defect in your air conditioner, then contact Athclimat company which will do the repair, installation, filling of your air conditioner in Moscow quickly and professionally.
To begin with, we need to make a brief excursus on the air conditioning system in the car and the principle of its work. During all existence of air conditioning systems the principle of operation has not changed, some variants of systems may have some distinctions and additional components, but the principle of operation is the same. The refrigerant (most often freon), under pressure is pumped into the condenser for cooling, there it becomes a liquid, after which it passes through a dryer, where small particles of dust, garbage and water, which could ever get into the system, are filtered out of the refrigerant. It is worth noting that the circuit through which freon is pressurized (compressor – condenser – dryer – thermostatic expansion valve) is a high pressure line, it is hot to the touch when the system is running. After the dehumidifier, the refrigerant passes through the TRV (thermostatic expansion valve), an automatic choke that creates a pressure drop and converts freon to gas. After the TRV, the icy freon passes through the evaporator in the car interior, whose main task is to take heat from the car interior and transfer it by means of the refrigerant to the condenser for cooling.
How to diagnose the air conditioner of your car with your own hands? There are cases when there is no possibility to ask for technical help from specialists or if you are used to troubleshooting systems of your car with your own hands – then the following instructions on diagnostics and troubleshooting are for you. 1. The first step is very important, do not neglect it – it is an inspection and cleaning of the entire air conditioning system from dirt and dust. At this stage it is necessary to inspect pipeline, compressor, evaporator, and condenser for mechanical damages, traces of compressor oil leakage, freon often leaks in such places. 2. The next step is to check if the compressor starts working. The air conditioner compressor is designed so that the drive pulley rotates all the time, and the compressor is connected to the pulley by a clutch on the electric drive. You need to start the engine, leave it running at idle and turn on the air conditioner, the load will increase and the engine speed will drop briefly. This indicates that the compressor clutch is good and the compressor is engaging. 3. Also it is very important to listen to the work of air conditioner compressor. There must not be any extraneous noises, if they are present, it is necessary to pass compressor for repair. 4. Further it is necessary to give to work with an air conditioner some minutes and to touch pipelines before and after compressor (be careful, there can be high temperature!), one should be hot and the second icy cold. This indicates that the components are working properly, but if it is still not cool in the cabin, it is necessary to check the work of air distribution systems in the car. 5. If the pipes are the same temperature or not significantly different, it is necessary to check the pressure in the air conditioner system, if necessary, to top up the refrigerant, repair the compressor. 6. 6. The dehumidifier of the air conditioning system can be equipped with a sight-glass, through which one can check the condition of the refrigerant in the system. Transparent condition of the refrigerant without bubbles is a correctly and fully charged air conditioner system. If there are bubbles or clouding of the refrigerant it is necessary to control pressure in the system, check it for tightness and top up if necessary. 7. Refrigerant leakage search is a rather difficult business, in car service conditions two most basic variants are used – gas catcher and specially painted gas, which glows in ultraviolet. In the first case, the search for the place of the leak is made by analyzing the gas, if the device picks up freon, it signals about it and you’ll be able to find the place of the leak by walking on the elements of the system. If the way of diagnostics with the help of the painted refrigerant is used, here also everything is very simple – the system of conditioner is charged with painted freon and in the ultraviolet light the place of a leak of the refrigerant becomes visible. Finding the place of leakage can be complicated due to its invisibility when, for example, the refrigerant is leaking very slowly, at certain modes of operation, it is necessary to take it into account. 8. Among typical reasons of reduced productivity or total failure of air conditioner one can also refer heavy contamination of condenser or evaporator. This leads to its improper operation, as well as the possibility of depressurization of the system due to the appearance of corrosion. 9.
There can also be problems with the thermostatic expansion valve, for this diagnosis it is better to contact a specialist. If you can not find the cause of the failure of the air conditioner yourself, we recommend you to go to a special repair shop, which specialists will help you to quickly find the problem and fix it.
Checking air conditioner tightness in the car with your own hands
It is not necessary to start the air conditioner during the check, if it is fully charged with refrigerant. But if the amount of freon is low, it is better to turn it on. If the device is leaky, then under the influence of increased pressure the liquid will start to come out. You can easily identify the place of the leak.
You can check the tubes of the car air conditioner for leaks and detect freon leakage on your own. To do this, use a pump, nitrogen, ultraviolet paint or a special device – a leak detector.
Easy ways of checking at home
Tightness of the air conditioner system on the car with their own hands check after continuous operation for at least 40 minutes, so that the device was under pressure.
Faulty auto air conditioner
Most often the unit leaks in the connection areas of the system elements. It is these places that should be carefully examined.
Pump
In the garage, you can check the tightness of the air conditioner in the car with your own hands with a pump for the split system. Siphon all the air from the device, check the level of minus pressure with a manometer and remember it. If in a day the indicator has not changed, there are no leaks.
Nitrogen
Checking the air conditioner of the car for tightness with your own hands is carried out with nitrogen. During the procedure, use a manometer.
The pressure should not exceed the norm of 17 bar, because when the indicator increases, the body of the split system may crack. Also, you can not turn on the device during the test, otherwise all the gas will go into the interior of the car.
Prepare a saturated soap solution (the liquid should bubble). To do this, take baby soap without dyes and distilled water. Preliminarily drain all freon from the split system.
- Check of automobile conditioner tightness with nitrogen is conducted the following way:
- Using the reducer, connect the gas can to the system and open the valve. Make sure that the nitrogen fills the air conditioner and does not escape into the interior of the car.
- Apply soapy solution with a brush or sponge on all possible places of leakage: pipes, hoses, connections, valves. The appearance of bubbles on any area indicates depressurization.
After the procedure remove all nitrogen.
It will not take more than 15 minutes to check air conditioner on tightness in your car this way.
Compressed air.
It is not recommended to test the auto air conditioner for leaks with this method. Compressed air has high humidity, so the refrigeration circuit of the split system can fail.
Leak Detector
The fastest way to check the tightness of the air conditioner with your own hands using a leak detector. But there must be at least a part of freon in the system.
Close all windows, bring the device near air conditioner and start slowly driving it. The leak detector is sensitive to Freon and will beep or glow (depending on the model) when it finds the leak.
Checking air conditioner tightness in the car with your own hands
It is not necessary to start the air conditioner during the test if it is fully charged with refrigerant. But if the amount of freon is low, it is better to turn it on. If the device is not tight, then under the influence of increased pressure, the liquid will begin to escape. You can easily locate the leak.
Ultraviolet lamp
To check the auto air conditioner for leaks, add fluorescent paint to the freon. Be sure to read its instructions so as not to exceed the rate.
After charging, let the air conditioner run for at least 40 minutes. Tinted Freon will appear on the outside of the unit if there is a leak.
