Do-it-to-yourself auto air conditioning refill requires eye protection, charging kit, refrigerant, and some good practical knowledge of the operation. However k you must have the manufacturer’s specifications and a charging manifold that has gauges, however, many people recharge their AC with kits available at some big stores and auto parts retailers.
- CHECK FOR ANY REFRIGERANT LEFT IN THE SYSTEM.To achieve this, fit a charging hose on the low pressure port, that is on the refrigerant line on the car, often close to the accumulator. Don’t forget to use eye protection. If the system is entirely discharged, it may be contaminated with moisture, and charging results would be less satisfactory unless the point of leak is found, repaired, and the receiver dryer is replaced. The open system needs to be repaired and drained using a vacuum pump to oust air and moisture. Compressor oil should be added if the system has been leaking. Signs of oil leakage and measurement of oil quantity left in a replaced compressor should be a guide on how much oil to replace.
- INSPECT FOR ANY OBVIOUS LEAKS.If there is much loss of refrigerant in the system, it may stop working, you have a leak. Minor leaks may take some months to reduce the refrigerant so that the AC stops to cool, however charging a system with a major leak is just a waste of time. Check for refrigerant oil residue on hose, tubes, and fittings that are components of the refrigerant system. Spray a soapy water on fittings and check for bubbles to appear, showing a leak.
- CHECK CONDENSING COILS FOR OBSTRUCTION WITH DEBRIS, AND FUNCTIONAL COMPRESSOR.To conduct a test of compressor with a low charge, jump the pressure switch, this is often located on the accumulator.
- TAP THE REFRIGERANT CAN.Do this by completely opening the valve on the tapping fitting, which retracts the tapping pin into the valve unit. Failure to this will lead to the tap puncturing the can during it is installation, releasing the refrigerant before the fitting is sealed.
- THREAD THE TAPPING VALVE ON THE REFRIGERANT CAN SECURELY.This forces the pin into the top of the can, making the release of the refrigerant when the valve is opened possible.
- PURGE OR DRAIN THE CHARGING HOSE.Screw open the valve until it is filled with refrigerant, then slowly loosen the brass component that connects the hose to the valve. Do not allow refrigerant to spray on bare skin, as this will cause the freeze skin tissue on contact. Be sure to re-tighten the hose when refrigerant start escaping; this should have forced any air from the hose.
- CRANK THE ENGINE AND TURN THE AC ON HIGH COOL, HIGH FAN.If the recharging hose is equipped with a pressure gauge, check to see if the system needs refrigerant. If the pressure is in the recommended range, the system is full and should not be recharged. But If the pressure is below the recommended range, follow the instructions on the operating manual to recharge the system.
- Another sign that the system needs refrigerant is when the compressor cycles rapidly. If the compressor turns on and off every 5 to 20 seconds, it is possibly out of low pressure. The pressure drops when the compressor kicks on, the compressor will shut off when the pressure becomes low, and the pressure goes back to the operating range as the system equalizes. Compressor cycling in a completely charged system should be very slow that is after every 30 seconds or up or not at all present because compressor stays on during hot weather.
- Know that if the cooling fans for the radiator are on and working while the AC system is on. If the compressor is on, the cooling fans should also be on hand to assist in cooling the Freon in the condenser, located either in front or behind the car radiator. Often, some cars have 2 fans, with one for the AC system.
- Allow the can to empty its contents.This usually takes from two to five minutes. The hotter the temperature outside, the more quickly the contents will empty. Leave the can with the tap up at all times, to make non-liquid refrigerant into the suction side of the system to avoid compressor damage. Be sure not to overcharge! Use a manifold gauge to measure both high and low side pressure. Check the pressure temperature chart.
- CLOSE THE VALVE AND DISCONNECT THE HOSE WHEN THE CAN IS DISCHARGED OR NO LONGER DISCHARGING ENOUGH TO KEEP THE CAN COLD.Inspect the charging port for leakages, and replace the plastic cap.
- CHECK THE AIR FROM THE AC VENTS INSIDE THE CAR.It should now be blowing cold (38-45 degrees), if not, maybe one can of refrigerant was not sufficient enough to charge the system, or some other system unit is faulty.