A/C Service Tips and Precautions (134a)

WARNING: 

• Compressed air mixed with the R-134a forms a combustible vapor.
• The vapor can burn or explode causing serious injury.
• Never use compressed air to pressure test R-134a service equipment or vehicle air conditioning systems.

WARNING: 

• Air conditioning refrigerant or lubricant vapor can irritate your eyes, nose, or throat.
• Be careful when connecting service equipment.
• Do not breathe refrigerant or vapor.

The air conditioning system uses HFC-134a (R-134a) refrigerant and polyalkylene glycol (PAG) refrigerant oil .

Use only service equipment that is U.L.-listed and is certified to meet the requirements of SAE J2788 to remove R-134a from the air conditioning system.

If accidental system discharge occurs, ventilate the work area before resuming service.

R-134a service equipment or vehicle air conditioning systems should not be pressure tested or leak tested with compressed air.

Additional health and safety information may be obtained from the refrigerant and lubricant manufacturers.

• Always disconnect the negative cable from the 12 volt battery whenever replacing air conditioning parts.
• Keep moisture and dirt out of the system. When disconnecting any lines, plug or cap the fittings immediately; do not remove the caps or plugs until just before you reconnect each line.
• Before connecting any hose or line, apply a few drops of refrigerant oil  to the O-ring.
• When tightening or loosening a fitting, use a second wrench to support the matching fitting.
• When discharging the system, use an R-134a refrigerant A/C recover/recycle/recharge machine; do not release refrigerant into the atmosphere.