Operation Procedure for Charging A/C with Refrigerant: Charge

WARNING: There is a risk of personal injury or health problems if the A/C system is charged with refrigerant incorrectly or if refrigerant containers are improperly handled.
Be sure to take the following precautions to reduce the risk of injury or health problems.

Be sure to perform the refrigerant charge operation with the engine stopped. Charge the high-pressure side first and then the low-pressure side. If you do not, the refrigerant may flow backward and cause the hose or refrigerant container to burst.
Install the tap valve carefully following the instructions on the refrigerant container to prevent contact with the refrigerant.
Be sure to empty the refrigerant container before discarding it to prevent possible health problems and other dangerous consequences.
Never expose the refrigerant container to a heat higher than 40 °C (104 °F). Liquid refrigerant will turn into a toxic gas.

NOTE: Failure to take proper precautions when charging the A/C system can result in charging the system with the incorrect amount of refrigerant and can lead to poor system operation or damage to system components.

Since the A/C system has no sight glass, first recover refrigerant and evacuate the system, and then fill the system with the specified amount of refrigerant.
Charge the system only when the compressor is not hot to assure that you have used the correct amount of refrigerant.
Be sure to check the pressure gauges before and during charging to assure that there is the correct amount of refrigerant in the system.
Do not turn the refrigerant container upside down during charging. Doing so will cause liquid refrigerant to enter the compressor and damage it.

NOTE: The A/C system contains HFC-134a (R-134a).
Described here is a method to charge the A/C system with refrigerant from the refrigerant service container.
When charging refrigerant recovered by using the refrigerant and recycling equipment (when recycling refrigerant), follow the procedure described in the equipment manufacturer's instruction manual.

Charge system with proper amount of refrigerant accurately in accordance with the following procedure.

Specified amount of refrigerant

530 ± 30 g (18.6 ± 1.0 oz)

The initial charging of the A/C system is performed from the high-pressure side with the engine stopped. And next, this method must be followed by charging from the low-pressure side with the engine running.

Check to make sure that hoses are routed properly after evacuating the system.
Connect low charging hose (1) and high charging hose (2) of the manifold gauge set (3) in position. Thus open refrigerant container valve (4) to purge the charging line.
Open the high-pressure side valve (6) and charge system with refrigerant.
After a while, open the low-pressure side valve (5) and close the high-pressure side valve (6).
WARNING: If the high-pressure side valve is not closed securely, the refrigerant may flow backwards and cause the hose or refrigerant container to burst, possibly resulting in a personal injury.
Be sure to close the high-pressure side valve securely.

Fig 1: Checking A/C System For Pressure Leaks
Courtesy of SUZUKI OF AMERICA CORP.
Start engine and keep engine speed at 1, 500 rpm. Then, operate A/C system.
Charge A/C system with refrigerant in vapor state. At this time, refrigerant container should be held upright.
When refrigerant container (3) is emptied, use following procedure to replace it with a new refrigerant container (3).
1. Close low pressure valve.
2. Replace empty container (3) with a refrigerant container which has been charged with refrigerant. When using refrigerant container tap valve (4), use the following procedure for replacement.
  1. Retract needle (1) and remove refrigerant container tap valve (4) by loosening its plate nut (2).
  2. Install previously-removed refrigerant container tap valve (4) to a new refrigerant container (3).
    
    Fig 2: Installing Refrigerant Container Tap Valve
    Courtesy of SUZUKI OF AMERICA CORP.
3. Purge any air existing in center charging hose.
  When using refrigerant container tap valve, use the following procedure to purge air.
  1. Once fully tighten refrigerant container tap valve and then loosen (open) plate nut slightly.
  2. Open low pressure valve of manifold gauge set a little.
  3. As soon as refrigerant comes out with a "hiss" (1) through a clearance between refrigerant container and tap valve, tighten plate nut as well as manifold gauge set low pressure valve.
  4. Turn handle of tap valve clockwise so that its needle is screwed into the new container to make a hole for refrigerant flow.
    
    Fig 3: Identifying Manifold Gauge Set
    Courtesy of SUZUKI OF AMERICA CORP.

After the system has been charged with specified amount (530 ± 30 g) of refrigerant or when low pressure gauge and high pressure gauge have indicated the following specified value, close low pressure side valve on manifold gauge set.

LOW SIDE AND HIGH SIDE PRESSURE EXAMPLE

Gauges should read as follows when ambient temperature is 30 °C (86 °F)
Pressure on high pressure gauge	1400 - 1595 kPa (14.3 - 16.3 kg/cm² ) (203 - 231 psi)
Pressure on low pressure gauge	260 - 374 kPa (2.7 - 3.8 kg/cm² ) (37.7 - 54.2 psi)