- Carefully attach the can tap to the refrigerant can by following the can tap manufacturer-s instructions.
- Disconnect the center manifold hose from the vacuum pump and connect the hose to the tap valve.
- If a 30 lb. (13.6 kg) container of refrigerant is used a weight scale will be needed. This scale is to determine the amount of refrigerant that is used. Connect the center hose from the manifold to the valve. Place the 30 lb. (13.6 kg) container on the scale, valve end down.
- Verify that all three hose connections are tight at the manifold gauge set.
- Open the valve on the HFC-134a source.
- Loosen the center hose connection at the manifold and allow the HFC-134a to escape for no more than two or three seconds, then quickly retighten the hose fitting at the manifold.
- Connect a tachometer to the engine.
- With the engine off, start charging by slowly opening the high-pressure manifold valve.
When both the high- and low-pressure gauge readings are about equal, or the HFC-134a source is empty, or the system has been filled to specifications, close the high-pressure manifold valve.
NOTEIf the HFC-134a source is exhausted, first close the high-pressure manifold valve, second, close the can tap valve, then slowly purge the refrigerant from the service hose by loosening the fitting at the can tap.
- Verify that the high-pressure manifold valve is closed (should have already been closed).
- Verify that the low-pressure manifold valve is closed (should have already been closed).
- With the A/C switch off and the windows rolled down, start the engine and run at idle rpm.
- Set the A/C controls on maximum cool and set the blower speed on the highest setting.
- Quickly turn the A/C switch on-off-on-off a few times to prevent initial compressor damage due to -load shock-. Finish this operation with the A/C switch in the ON position.
- Raise engine rpm to approximately 1,500 rpm.
- With the refrigerant source connected and the service hose purged, slowly open the low-pressure manifold valve, while checking the low-pressure gauge reading.
- Keep the low side pressure below 40 psi (276 kPa) by using the low-pressure manifold valve to regulate the flow of refrigerant into the system.
- When the system is fully charged, close the low-pressure manifold valve.