Charging New R-134a Refrigerant

WARNING: This page is about a different car, the 2002 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION:

Do not exceed the specification when charging the system with refrigerant. Doing so will decrease the efficiency of the air conditioner or damage the refrigeration cycle parts.

Install the manifold gauge set.
Connect the tap pin side of the charging hose to the air purge valve of the manifold gauge.

Fig 1: Purging Air From Manifold Gauge
Courtesy of MAZDA MOTORS CORP.
Connect the vacuum pump hose to the center joint of the manifold gauge.

Fig 2: Connection Vacuum Pump To Manifold Gauge
Courtesy of MAZDA MOTORS CORP.
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 3: Opening All Valves On Manifold Gauge
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 backflow 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.
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.
Check the high- and low-pressure side readings of the manifold gauge.
- If the reading has changed, check for leaks and then repeat from step 7 .
- If the reading has not changed, go to step 12.
Open the valve of the refrigerant tank.
Weigh the refrigerant tank to charge the suitable amount of refrigerant.
Regular amount of refrigerant (approximate quantity)

750 g {26.5 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.
Open the low-pressure side valve of the manifold gauge.

Fig 4: Opening Low Pressure Valve On Manifold Gauge
Courtesy of MAZDA MOTORS CORP.
When the high-pressure side reading increases to 0.098 MPa {1.0 kgf/cm ² , 14 psi} , close the low-pressure side valve of the manifold gauge.

Fig 5: Closing Low Pressure Valve On Manifold Gauge
Courtesy of MAZDA MOTORS CORP.
Check for leaks from the cooler pipe/hose connections using a gas leak tester.
- If there are no leaks, go to step 18 .
- If a leak is found at a loose joint, tighten the joint, go to next step.
Check for leaks again.
- If there are no leaks after tightening the joint, go to next step.
- If there is still a leak at the same joint, discharge the refrigerant and then repair the joint. Repeat the charging procedure from step 7 .
WARNING:
- If charging the system with refrigerant using 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.
Open the low-pressure side valve of the manifold gauge and charge with refrigerant until the weight of refrigerant tank has decreased 350 g {12.4 oz} from the amount in step 13 .

Fig 6: Opening Low Pressure Valve On Manifold Gauge
Courtesy of MAZDA MOTORS CORP.
Close the low-pressure side valve of the manifold gauge.

Fig 7: Closing Low Pressure Valve On Manifold Gauge
Courtesy of MAZDA MOTORS CORP.
WARNING:
- 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.
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 750 g {26.5 oz} from the amount in step 13 .

Fig 8: Opening Low Pressure Valve On Manifold Gauge
Courtesy of MAZDA MOTORS CORP.
Close the low-pressure side valve of the manifold gauge and the valve of the refrigerant tank.
Stop the engine and A/C compressor.
Check for leaks from the cooler pipe/hose connections using a gas leak tester.
- If there are no leaks, go to step 26.
- If a leak is found at a loose joint, tighten the joint, go to next step.
Check for leaks again.
- If there are no leaks after tightening the joint, go to next step.
- If there is still a leak at the same joint, discharge the refrigerant and then repair the joint. Repeat the charging procedure from step 7 .
Remove the manifold gauge set.
Install the caps to the charging valves.

Fig 9: Removing Manifold Gauge & Installing Charging Valve Caps
Courtesy of MAZDA MOTORS CORP.