Heating and Air Conditioning: Service Precautions

SAFETY PRECAUTIONS




The following safety precautions should be observed when working on an automotive refrigeration system:

- Always wear eye protection and gloves while handling refrigerant or servicing an air conditioning system.
- Avoid breathing R-134a vapor or mist; exposure may irritate eyes, nose, throat, and lungs.
- If refrigerant or compressor oil contacts the skin or eyes, rinse the affected area with warm water; administer first aid immediately, and consult a doctor.
- Use only approved service equipment to discharge A/C systems.
- If an accidental discharge occurs, ventilate the work area.
- Store refrigerant service equipment and bulk supply containers in a cool, dry location away from direct sunlight and other heat sources (<113°F, (45°C)).
- Do not expose refrigerants to an open flame, since burning refrigerant can produce poisonous gas. This includes open flames (such as in a propane leak detector), portable heaters, and lit cigarettes.
- Do not pressure-test service equipment or vehicle A/C systems with an air/R-134a mixture. Some mixtures of air and R-134a are combustible at elevated pressures. The use of compressed air for leak detection in an R-134a system could result in a fire or explosion.
- Do not discharge refrigerant into the atmosphere; contain it. R-134a is heavier than air; if discharged into the atmosphere, it can replace the air, causing suffocation. If R-12 is discharged into the air it damages the environment.
- Never weld or steam-clean any part of the air conditioning system. Heating the refrigerant in a closed system could cause an explosion, due to the increased pressure.
- Always consider R-12 or R-134a to be under high pressure, whether in the automobile refrigeration system, service equipment, or refrigerant storage containers.
- R-134a should only be handled by competent, informed personnel using approved procedures and equipment. Failure to do so may result in serious injury and/or substantial equipment or vehicle damage.
- Removal of R-134a must be carried out using R-134a equipment that meets the requirements of SAE J2210.
- If accidental discharge occurs, ventilate the work area before resuming service. Exposure to high concentrations of refrigerant vapor can induce anesthetic effects such as weakness, dizziness, and nausea.







The R-134a service fittings are a unique design and prohibit the connection of non-approved equipment. The large diameter metric fitting is the high side (also sight glass) while the smaller diameter fitting is the low side.







The ACR4 unit has approved quick disconnect hose connectors which correspond to the special R-134a service fittings found on the vehicle. This arrangement prevents the accidental connection of R-12 service equipment.
No attempt should ever be made to bypass these special fittings

Refer to S.I.B. # 641392 (3646) for nominal air conditioning system pressures R12/R134a