A/C - Handling Precautions For Freon R-12

90mitsubishi02 SUBJECT:

R-12 HANDLING
NO. TSB-90-55-001

DATE February, 1990

MODEL All

PURPOSE

This bulletin emphasizes the safety and handling precautions that the servicing technician must use when handling Freon R-12.

SAFETY PRECAUTIONS

The refrigerant used in all Mitsubishi Motors air conditioners is R-12. It is transparent and colorless in both the liquid and vapor state. Since it has a boiling point of -29.8 degrees C (-21.7 degrees F), at atmospheric pressure, it will be a vapor at all normal temperatures and pressures. The vapor is heavier than air, nonflammable, and not explosive. It is not poisonous except when it is in direct contact with an open flame. It is noncorrosive except when combined with water.

CAUTION WEAR SAFETY GOGGLES WHEN SERVICING THE REFRIGERATION SYSTEM OR HANDLING R-12.

R-12 evaporates so rapidly at normal atmospheric pressures and temperatures that it tends to freeze anything it contacts. For this reason, extreme care must be taken to prevent any liquid refrigerant from contacting the skin and especially the eyes. Always wear safety goggles when servicing the refrigeration part of the air conditioning system. Keep a bottle of sterile mineral oil handy when working on the refrigeration system. Should any liquid refrigerant get into the eyes, use a few drops of mineral oil to wash them out. R-12 is rapidly absorbed by the oil. Next, splash the eyes with plenty of cold water. Call your doctor immediately even though the irritation has ceased.

CAUTION DO NOT HEAT R-12 ABOVE 52 degrees C (125 degrees F).

In most instances, moderate heat is requiredto bring the pressure of the refrigerant in its container above the pressure of the system when charging or adding refrigerant. A bucket or large pan of hot water not over 52 degrees C (125 degrees F) is all the heat required for this purpose. Do not heat the refrigerant container with a blow torch or any other means that would raise temperature and pressure above this temperature. Do not weld or steam clean on or near the system components or refrigerant lines.
CAUTION KEEP R-12 CONTAINERS UPRIGHT WHEN CHARGING THE SYSTEM.

When metering R-12 into the refrigeration system, keep the supply tank or cans in an upright position. If the refrigerant container is on its side or upside down, liquid refrigerant is likely to enter the system and may damage the compressor.

CAUTION ALWAYS WORK IN A WELL VENTILATED ROOM.

Good ventilation is vital in the working area. Although R-12 vapor is normally nonpoisonous, contact with an open flame can cause the vapor to become very poisonous. Do not discharge large quantities of refrigerant in an area having an open flame as used in some water heaters or hot tanks. A poisonous phosgene gas is produced when R-12 is exposed to open flame, as when using a flame-type leak detector as opposed to an electronic type. Avoid inhaling the fumes from the flame-type leak detector.

CAUTION DO NOT ALLOW LIQUID REFRIGERANT TO TOUCH BRIGHT METAL.

Refrigerant will tarnish bright metal and chrome surfaces, and in combination with moisture can severely corrode all metal surfaces.

NOTE R-12 REFRIGERANT RECYCLING

R-12 refrigerant is a chlorofluorocarbon (CFC) that can contribute to the depletion of the ozone layer in the upper atmosphere. The ozone layer filter out harmful radiation from the sun.

To assist in protecting the ozone layer, the manufacturer recommends that a R-12 refrigerant recycling device that meets SAE standard J1991 be used when the refrigerant is taken out of a system.

Refer to the operating instructions provided with the recycling equipment for proper operation. If it is not possible to recover the ref figerant when evacuating a system, always discharge the refrigerant into the service bay exhaust system or outside the building. Large quantities of refrigerant vapor in a small, poorly ventilated area can displace the air and cause suffocation.