Charging New R-134a Refrigerant

WARNING: This page is about a different car, the 2003 Mazda Protege5 and 2003 Mazda Protege. However, it is still accessible from the selected car via links, so may be relevant.

Install the manifold gauge set.
Connect the tap pin side of the charging hose to the air purge valve of the manifold gauge.
Connect the vacuum pump hose to the center joint of the manifold gauge.
Connect the vacuum pump hose to the vacuum pump.
Connect the charging hose to the refrigerant tank.
Place the refrigerant tank on the scale.
Open all the valves of the manifold gauge.

Fig 1: Identifying Refrigerant Charging Components
Courtesy of MAZDA MOTORS CORP.
CAUTION:
- Close the manifold gauge valve immediately after stopping the vacuum pump. If the valve is left open, the vacuum pump oil will back flow into the refrigeration cycle and cause a decrease in the efficiency of the air conditioner.
Start the vacuum pump and let it operate for 15 minutes.

Fig 2: Identifying Vacuum Pump
Courtesy of MAZDA MOTORS CORP.
Verify that high-and low-pressure side readings of the manifold gauge are at -101 kPa {-760 mmHg, -29.9 inHg}. Close each valve of the manifold gauge.
Stop the vacuum pump and wait for 5 minutes.
Inspect the high- and low-pressure side readings of the manifold gauge.
- If the reading has changed, inspect for leakage and then repeat from Step 7 .
- If the reading has not changed, and go to next step.
Open the valve of the refrigerant tank.
Weigh the refrigerant tank.

Fig 3: Inspecting The High- And Low-Pressure Side Manifold Gauge Readings
Courtesy of MAZDA MOTORS CORP.

Regular amount of refrigerant (approximate quantity) 525 g {18.6 oz}
WARNING:
- If the refrigerant system is charged with a large amount of refrigerant when checking for gas leakage, and if any leakage should occur, the refrigerant will be released into the atmosphere. In order to prevent the accidental release of refrigerant which can destroy the ozone layer in the stratosphere, follow the proper procedures and charge with only a small amount of refrigerant when checking for gas leakage.
- If charging the system with refrigerant by service cans or refrigerant tank, running the engine with the high-pressure side valve open is dangerous. Pressure within the service cans or refrigerant tank will increase and they could explode, scattering metal fragments and liquid refrigerant that can seriously injure you. Therefore, do not open the high-pressure side valve while the engine is running.
CAUTION:
- Always begin charging of refrigerant from the high-pressure side. If charging is begun from the low-pressure side, the vanes of the A/C compressor will not be released and abnormal noise may result.
Open the high-pressure side valve of the manifold gauge.

Fig 4: Opening Manifold Gauge The High-Pressure Side Valve
Courtesy of MAZDA MOTORS CORP.
When the low-pressure side reading increases to 0.098 MPa {1.0 kgf/cm ² ,14 psi}, close the high-pressure side valve of the manifold gauge.
Inspect for leakage from the cooler pipe/hose connections using a gas leak tester.
- If there is no leakage, go to Step 18 .
- If leakage is found at a loose joint, tighten the joint, then go to the next step.
Inspect for leakage again.
- If there is no leakage after tightening the joint, go to the next step.
- If there is still a leakage at the same joint, discharge the refrigerant and then repair the joint. Repeat the charging procedure from Step 7 .
Fig 5: Inspecting Cooler Pipe/Hose Connections Leakage
Courtesy of MAZDA MOTORS CORP.
WARNING:
- If charging the system with refrigerant using service cans, running the engine with the high-pressure side valve open is dangerous. Pressure within the service cans will increase and the cans could explode, scattering metal fragments and liquid refrigerant that can seriously injure you. Therefore, do not open the high-pressure side valve while the engine is running.
Open the high-pressure side valve of the manifold gauge and charge with refrigerant until the weight of refrigerant tank has decreased 300 g {10.6 oz} from the amount in Step 13.

Fig 6: Opening Manifold Gauge The High-Pressure Side Valve And Charging Refrigerant
Courtesy of MAZDA MOTORS CORP.
Close the high-pressure side valve of the manifold gauge.
WARNING:
- If charging the system with refrigerant using service cans, running the engine with the high-pressure side valve open is dangerous. Pressure within the service cans will increase and the cans could explode, scattering metal fragments and liquid refrigerant that can seriously injure you. Therefore, do not open the high-pressure side valve while the engine is running.
Fig 7: Closing Manifold Gauge High-Pressure Side Valve
Courtesy of MAZDA MOTORS CORP.
Start the engine and actuate the A/C compressor.
Open the low-pressure side valve of the manifold gauge and charge with refrigerant until the weight of the refrigerant tank has decreased 525 g {18.6 oz} from the amount in Step 13.
Close the low-pressure side valve of the manifold gauge and the valve of the refrigerant tank.
Stop the engine and A/C compressor.
Inspect for leakage using a gas leak tester.
- If there is no leakage, go to Step 26 .
- If leakage is found at a loose joint, tighten the joint, go to the next step.
Fig 8: Inspecting Leakage Using Gas Leak Tester
Courtesy of MAZDA MOTORS CORP.
Inspect for leakage again.
- If there is no leakage after tightening the joint, and go to the next step.
- If there is still leakage at the same joint, discharge the refrigerant and then repair the joint. Repeat the charging procedure from Step 7 .
Disconnect the quick couplers from the charging valves.
Install the caps to the charging valves.

Fig 9: Installing Caps To The Charging Valves
Courtesy of MAZDA MOTORS CORP.