REFRIGERANT CHARGING PROCEDURE IN AUTOMOTIVE We recommend reading this procedure completelyYou may need information before charging you want toHave this procedure with you while charging. Although it can be done by a single person, we recommend having a helper around. This procedure outlines the steps to performThese steps are not to be used to refill or make partialToping off requires system parameters monitoring and knowledge, speciallyExcessive gas will harm your system and will keep itMORE REFRIGERANT DOES NOT MEAN COLDER TEMPERATURES CHARGING IN GAS OR LIQUID - Please Do not use the sightglass (if so equipped) in R134a-based systems as if were R-12 based. 2) Gauges (R12 or R134a) 3) Service port adapter (as required in most R12-based systems) R134a systems do not require adapters other than the couplers in your gauges in the majority of applications 4) Refrigerant gas (R12 or R134a) 5) Optional: 2-3 ounces of specified oil.

1. Make sure what is the required amount ofFrom factory, all systems have a decal under the hood that give the data. If the decal is missing or you are not sure, please specify make, model, and the type of refrigerant used and whether your system is a factory or an after marketIt is very important to know if your system has oil. Oil starvation is the main reason of compressorOil can be added to the system in two ways: with oil injectors or throughbest brand home ac units the low side port under vacuum. ac units for the windowThe procedure to add oil through vacuum is describedair conditioner and heater not working in car and other useful specifications are provided here. 2. Connect both blue and red gauge hoses to

the system's service ports. The discharge port (red hose) is located somewhere between the compressor and expansion device, either before the condenser orIn R134a systems, the port is the thicker of both, while in R12 systems is the thinner one. In some aftermarket systems, the port is located in the back of the compressor. If your ports are located in the compressor, the low side is marked by an "S" and the high side by an "H". caps have an "L" for low or "H" for high. 3. Open both gauge valves. hose (yellow one) to the vacuum pump. Make sure both gauge needles are zeroedNeedle is adjusted by turning a fine screw inside the dial. the plastic lens to do this. 4. Turn the pump on. You'll notice that both gauge readings begin to drop. The blue gauge's needle will even dip into negativeThe desired low side reading should be less than -25, while the high side will remain at 0. 5. After approximately 5 minutes, close bothTurn the pump off, and observe the needles.

The faster the movement, the greater the loss. two minutes you don't see any needle movement, open both valves, turn the pump on, and continue vacuum for not less than 30 minutes. Close both valves then turn the pump off. 6. Get ready to charge. Have the necessary refrigerantCans make charging easier and more precise unless you have a charging cylinder or a precision scale. 7. Disconnect the yellow hose from the vacuum pump and connect it to the can tap or charging cylinder valve. in two ways: liquid (can upside down) or gas. Liquid charging is a lot faster but not recommended unless you extreme care or have experience. (gas) charging is slower but safer. 8. Once you've decided, and with the can or container connected, unscrew the top yellow hose connection (at the gauges) allowing refrigerant to escape for a couple of seconds. This will purge the air out of the hoses so you make sure that all you dispense is refrigerant.

You can do this venting in liquid form so you can see when a fine, steady stream of refrigerant escapes indicating that all the air is gone from the hose. breathe refrigerant and don't charge in a flammable environment. 9. "Flood" the system with liquid refrigerant (can upside down) by opening the red valve (high side) until itClose the red valve. Jump the low pressure cycling switchIf you don't know what this is or where it is, ask for help 10. Turn the engine on. Turn the A/C into MAX on its third or higher blower speed. You'll note that both gauge readings areThe red gauge should read between 100 and 150, while the blue gauge between 5 and 15. If you are charging with cans, don't forget to purge air out the hose after hooking a new can as described in step 8 above. charge will continue through the low (blue) side (see note below)If you haven't jumpered any switch (you don't have to), you'll notice the compressor cycling frequently on and off.

will disappear as you dispense more refrigerant. The only disadvantage of frequent compressor cycling is that charge will take longer. Needles will move up and down with every cycle. Do not jump any switch unless you are NEVER OPEN THE RED VALVE WHILE CHARGING. The red valve is to be opened only during pre-charge, vacuum, or when a systemIts function is keeping an eye on the high side only. be closed at all times. If you have any doubts, wait until you receive information. Severe injury or death may occur. Remember: ALWAYS wear safety goggles. charge your system in a closed environment. There are two ways to charge: gas (can or cylinder up), or liquid (can or cylinder upside down). is designed to compress gas. Direct liquid charge will harm the compressor if suction pressure is not controlled. Liquid charging is faster, yet is riskier. Liquid charging should be made by professionals or under supervision. charging can be done if the suction port is away from the compressor (some compressors

have the suction valve in its body). Liquid charging can be done never exceeding a 50 PSI suction pressure. If you can't control it, charge in gasIn cooler weather, cans may freeze. You may immerse them in water and shake them while charging. about 2/3 of the charge has been dispensed into the system, spray water in the condenser to optimize heat exchange and speed the process. When you get the condenser wet, vent temperature is likely to raise. note pressure drop in both gauges. 12. Once the specified amount has been dispensed, close the blue valve. Let the system run for a minute. Turn the A/C off andWait another minute and disconnect the couplers from the serviceDisconnect the low side first. If you jumpered a switch, reconnect it Optimum cooling performance is attained after 10 minutes of operation. Our own acceptance criteria is at least 50�F in the center vent to the driver side at idle after 10 minutes or less.

cooling increases while the vehicle is in motion. Due to the physical properties and chemical composition, R134a and R12 charging amounts are different. if you are retrofitting, charge the same or specified amount of R12 with R134a. If in doubt, please e-mail us here. Do not use this procedure if you are using any other refrigerant. This is just for R12 or R134a. Although procedures and parameters may be similar, we do not use nor HOW TO DETERMINE OPERATING PRESSURES Every vehicle has its own operationDepending on whether or not the vehicle has a factory or an after market system, and whether it was retrofitted or is still original,There is no established calculation to determine the exact operating The low pressure (blue gauge) should be 35 or less at idle, regardless of the type of gas. Only if you're running a dual system, the low pressure may be between 45 and 50 at idle. The high pressure, for starters, is directly related to ambient temperature: the higher the temperature, the higher

the higher the pressure. Bear in mind that dispensing a complete charge without lowering the pressures with water will result in higher readings. is normal, and that is why you should spray water in the condenser at 2/3rds of the charge or once you have completed it. You'll note an immediate pressure drop when you spray water in the condenser. To obtain a ballpark high side value, multiply ambient temperature by 2.2 if you have an R12 system. If you have a factory R134a system, use 2.3. To convert �C to �F, use this formula: �C X 1.8 + 32. Remember: this is only a ballpark. we have factory charts to help you determine the correct pressures. your vehicle's make, model, refrigerant type, and year and click Factors like a an obstructed or very dirty radiator and condenser, weak or inoperative fan clutch, weak or inoperative radiator fan(s), either electric or mechanical, will make pressures go up and impair