If your car or truck A / C does not blow "cold air", the first thought is to panic. $ $ $ $ Signs will go through your head. A / C is broken and the repair will be expensive. This article is the secret of air conditioning systems of cars, and serves as a primer, so that together we can repair and save money on professional repairs.
A / C Principles
There are books and publications, the amount of information on air conditioningfor repair. This information is often too technical for you to learn how to repair the automatic climate control.
In short, here's everything you need to know the fundamentals of refrigeration, so you can fix your car air conditioner alone.
The air conditioning is the process in which cool the air in the passenger compartment, dried and put into circulation. The heat is removed from inside the vehicle and the outside air.
All air conditionersif there is an automatic A / C, household refrigerator at home or at work on the same principles HVAC. This means that changing a liquid refrigerant into gas and then back to a liquid. If a change of state is to take place of the coolant, heat transfer takes place. The two (2) the rules that apply to refrigerant:
1 Refrigerant in a gaseous state collects, absorbs and retains heat.
2 Refrigerant liquid releases the heat.
A / C operation and components
For Your Auto A / Cto blow "cold air", the R-134a must pass the state and the change in three (3) components, one (1) receiver and a hairdryer (1) expansion valve, the closed car-conditioning. The system components are:
1 Compressor - A device, the refrigerant is heated under pressure ..
2 Capacitor - A radiator for cooling, heat is absorbed into the passenger compartment to the transfer of colder air.
3 Evaporator - It's a little coolerlocated under the dash in the passenger compartment. Liquid refrigerant in the evaporator produces a pressure drop. The liquid refrigerant absorbs heat from the air that blows over the evaporator. Then bubbles and changes its state of steam before it enters the compressor suction.
4 Receiver-drier - is a container that contains the liquid refrigerant when the compressor is not running. It contains a desiccant, the moisture from the system.
5 Expansion valve - This is aMetering device which controls the amount of refrigerant to the evaporator.
A / C Quick Check
A check will be easy for the health of the A / C system control is the "sense of control." With the engine running, turn off the automatic A / C "ON" and the fan on "high". Take a test ride on the engine warms up the A / C system pressures to stabilize. Raise the hood. In the A / C "On", the pursuit of great pipes connected and moved by the compressor (low side) to the expansion valve (inputSide) of the evaporator. Then, locate the small pipe, the exhaust side of the compressor and is connected to the evaporator. If you think that these two (2) the lines, you should see these results:
1 The low-side line is to be "cool" under control.
2 The high-side line should feel "hot".
If the high-side hose is not hot and the bottom is not cool, will need more evidence, because the system will not work. Sinceis an internal problem, such as a defective component or a leak in the A / C system
A / C
Before testing the temperature of the system can be done, should be followed by a checklist (see below) in order to test the A / C System:
1 Set the A / C "ON-OFF" switch to "ON".
2 Set the temperature control to "maximum cooling."
3 Set the fan on "high" or the highest number on the controller.
4 The temperature inside the car must be stable and alwaysCooler.
5 The engine is a minimum of 1500 revolutions per minute will be.
6 All windows must be set to "UP".
Check the temperature
Its compact car or truck has a low capacity of A / C and a loss of "cool" more evident with greater ability Car A / C would. If a significant loss of ability to "cooling" is observed, a temperature control can be done at the vent registers. This can be read with a digital thermometer or instant they are made .. The reliefAir from the fans inside the passenger compartment should be 38-42 ° C.
A / C system diagnostics
Assuming that the test is measured in the exhaust vent off the register, a pressure test of the system must be done. Professional A / C as a tool to connect the great variety of measures set to "low" side service valves and "high" of the system known. Diagnose and for you to watch the A / C, you will need to be proficient in the use of multipleGauge September
A set manifold gauge, which is suitable to the needs can be purchased for less than $ 50.00 in stores fronts more cars and Internet Tool A / C and supply store. TIP: Look for a set theory that has a built-in sight glass.
Look for the "low" and "high" side service valves .. Near (have a connector suitable for shooting), the service pipes to the valves as follows.
1 Connect the blue tube of the toolset, the valve "low-side" service the compressor.
2Connect the red tube to set the counter, the '"high-side service valve of the compressor.
3 The yellow tube of the meter is set to a vacuum pump or refrigerant coolant can be added with this system. The yellow pipe is not connected to the system at this time.
Static test
If you find an out-of-range temperature measurement, the multiple indicator set to "low" and "high-side" service valve should be installed. With the engine "OFF" and not the compressor and clutchengaged, the blue "low side" and red "top" should display the same reading level of about 80 to 120 psi These readings indicate that there is a refrigerant in the A / C system If the readings were 50 psi on every track, this would indicate that the coolant in the system, but a small fee. If the readings were 10 to 20psi in each meter would mean that there is little or no coolant in the system A / C.
Engine running test
Start the engine. Once again, theA / C "ON" switch with the fan on "high" and run for a minimum of fifteen (15) minutes. Watch the display on the set pressure gauge manifold. TIP: A versatile measuring instrument with built-in sight glass (see above) is set to save time of diagnosis, because most of A / C systems are not built on a light on the receiver-dryer on the high side of the plant.
This function is to try the oil cooler and coolant bubbles in the glass view of the distributor. The oil moves through the glass wouldshow that the compressor and the clutch is actuated. Refrigerant is moved on the low side of the A / C system in the refrigeration circuit.
Small fee
It is installed with the engine running, A / C switch to "ON", and the great variety of measuring instruments, would be a "low side" pressure reading of 20psi over 150psi suggest that your A / C system has a charge low. The reading 150psi down on "high side" indicator would tell the story that the system is doing very little work. A small fee is usuallyis an indicator that there is a loss of coolant from one component to the "low" or "top" of the A / C. A loss of coolant in the system would need for A / C system to blow "cold air" to be repaired. TIP: do not consume refrigerant, expires. Some symptoms appear for a small fee for the state:
1 compressor clutch cycling short.
2 Clutch does not engage.
3 little or no cooling.
4 residues of oil pipes and components.
Loss control
For yourA blowing system / "cold air" C, refrigerant leaks must be found and repaired. Typically, the losses in the A / C system smaller and can be solved with a screwdriver or hand tools. Most A / C use Schrader valves for easy connection of the set pressure gauge manifold. That is, these are only covered bicycle valves, a valve core. If the test of a system, the valves will consider first whether a loss. Other objectives, such as residual oil pipes connected to the compressoris the second place that should be controlled. TIP: When tightening the screws with the intake and exhaust of the compressor by hand, do not overtighten. 0-rings, rubber suction and discharge of the compressor connected to the seal. The seals will be a loss if tightened too much. Just pull comfortably.
If the A / C system has a low load, a refrigerant must be added to control the loss. Refrigerant, which contains a dye for leak testing of a system that isused for this purpose. The set of measurement manifold, coolant, and a mixer can leverage you need to add coolant to a leak in the system.
Close the instrument manifold as described above. Connect the yellow hose to the valve seat and the valve can be earlier (clockwise) the valve. Connect the blue trace on the set pressure gauge manifold. Open the valve on the can tap valve. Slowly open the valve on the blue or such "low-side" and let the flow of refrigerant from the refrigerantSystem until a reading of 60psi on the "low side" caliber. TIP: If you, the refrigerant is in a pot with hot water vapor is the refrigerant in the A / C system type faster. WARNING: Do not turn around, the refrigerant can. Thus, the liquid refrigerant, a compressor system will be ruined.
Professional A / C use an electronic leak detector to find leaks in the system. Use a battery leak detector kits UV and UV goggles. This kit canAuto stores and Internet A / C supply store fronts are obtained.
UV protection glasses are in control of losses. Simply insert the tip of the detector assembly, or port are checked at each component of the A / C. If a leak is found, a light green color due to UV protection glasses to see.
Airflow
One often overlooked reason for your A / C does not blow "cold air" is debris that clog the condenser. Bugs, plastic bags, and leaves the cityand driving on the freeway, the air is out, to avoid through the radiator fins. The condenser should be cleaned with a detergent solution. Bent fins on the condenser should be smoothed with a finger tip.
Limitations
A constraint is a condition that a block. It is usually due at the exit of the condenser. Any form of deposits was formed leading to a restriction of refrigerant through the condenser tubes .. The steps in the tubes of most capacitorsused in compact cars and trucks are very small. An effective way to create a restriction in your A / C system is to diagnose the series manifold. The "top" would be (red) measures to move into the danger zone to about 300 psi.
System Repair
If a system has been opened, and a component is removed, the moisture has entered the system. Strike A / C to "cold air", the moisture must be removed with a vacuum pump.
In this phase of repair, you have to end two (2) decisionsrepair the A / C. The first choice is professional with the car or truck to an A / C. In their work, they will evacuate the system, check your work, and charge the A / C system charge.
The second way is to change your A / C system is repaired. You need to borrow or buy a vacuum pump to complete the repair. A small two-stage vacuum pump, which was developed for automotive cooling systems, is available for less than $ 100.00.
After replacing a component, moisture isin the system during repairs. The need for A / C system to blow "cold air" to remove moisture. Install the manifold gauge set for your car or truck service valves as described above. After repair the A / C system is evacuated and recharged by applying the following steps:
1 tube blue for the "lower" service valve.
2 red tube "high-side service valve.
3 yellow hose to the intake port of the vacuum pump.
4 Close the manual valve to the vacuumPump.
5 back seat (open) the valve hand on blue and red indicators on the set pressure gauge manifold.
6 Connect the power supply of the vacuum pump.
7 Open the valve on the hand vacuum pump.
8 Run the vacuum pump for three (3) minutes.
9 The needle on the "low side" indicator (blue) show should be in a vacuum 28.3hg.
10 A system with a vacuum leak will pull 28.3hg in three (3) minutes.
11 If the fall does not 28.3hg gauge of blue,The evacuation must be stopped because there is a leak in the car or truck A / C system
12 The loss will be found in the A / C system with UV detector and UV glasses.
13 After the leak is found and corrected, continue the evacuation procedure is as described above for 25 minutes.
14 Front seat (close) the hand valves on the blue and red markers and watch the needle on the blue run.
15 The needles should adhere to 29hg stable, suggesting a system of close cooperation withlosses.
Every movement in the direction of the needle 16 '0 "blue" low side "indicator may indicate a leak in the system and the evacuation was canceled, and the search for the loss.
Manual 16.Look 'I know the factory service manual for recommended refrigerant. Usually it is 16-28 grams.
17.Attach valve can open a can of refrigerant, make sure that the valve nozzle is positioned in front of the hand (closed).
18 Switch off the A / C control"ON" and fans of "high".
19 Start the engine and run at 1500 rpm is.
20 Set up the coolant in a pan of hot water. Warning: can not deny this process as a liquid entering the system and ruin the compressor reed valves.
21 Repeat this process came into the factory, freight (about 2 1 / 2 cans) of the system.
22 Turn off the engine car or truck and let the A / C system to stabilize. If the readings on red andBlue teachings are the same, remove the blue "low side" of the tube service valve.
23 Start the engine and remove the red "high side" hose from the service valve.
24 Close the hood and take the car or truck for a three (3) Mile Drive test.
25 instant-read thermometer or a digital record in the air in the passenger compartment.
26 The temperature should be 38-42 degrees centigrade degrees within 90 days.
Tools and materials
1 ManifoldTogether
2 Vacuum pump
3 Hand Tools
4 battery-powered UV leak detector
May 5 mixer
6 134th dye
7 134th
Instant Read Thermometer 8
9 Digital Thermometer
