Technician Safety Information

The Freon refrigerant used is also known as R-12. It is odorless and colorless both as a gas and a liquid. Since it boils (vaporizes) at - 21.7 °F, it will usually be in a vapor state when being handled in a repair shop. But if a portion of the liquid refrigerant should come in contact with the hands or face, note that its temperature momentarily will be at least - 22 °F.

WARNINGS:
Protective goggles should be worn when opening any refrigerant lines. If liquid coolant does touch the eyes, bathe eyes quickly in cold water, then apply a bland disinfectant oil to eyes. See an eye doctor.

When checking a system for leaks with a torch type leak detector, do not breathe vapors coming from flame. Do not discharge refrigerant in an area of a live flame. A poisonous phosgene gas is produced when R-12 is burned. While the small amount of gas produced by a leak detector is not harmful unless inhaled directly at the flame, the quantity of refrigerant released into the air when a system is purged can be extremely dangerous if allowed to come in contact with an open flame. Thus, when purging a system, ensure that the discharge hose is routed to a well ventilated place where no flame is present. Under these conditions the refrigerant will be quickly dissipated into the surrounding air.

Never allow the temperature of refrigerant drums to exceed 125°F. The resultant increase in temperature will cause a corresponding increase in pressure which may cause the safety plug to release or the drum to burst.

If it is necessary to heat a drum of refrigerant when charging a system, the drum should be placed in water that is no hotter than 125 °F. Never use a blow torch or other open flame. If possible, a pressure release mechanism should be attached before the drum is heated.

CAUTIONS:
When connecting and disconnecting service gauges on A/C system, ensure that gauge hand valves are fully closed and that compressor service valves, if equipped, are in the back-seated (fully counterclockwise) position. Do not disconnect gauge hoses from service port adapters, if used, while gauges are connected to A/C system. To disconnect hoses, always remove adapter from service port. Do not disconnect hoses from gauge manifold while connected to A/C system, as refrigerant will be rapidly discharged.

After disconnecting gauge lines, check the valve areas to be sure service valves are correctly seated and Schrader valves, if used, are not leaking.

The system must be completely discharged before opening any fitting or connection of the refrigeration system. Open fittings with caution even after the system has been discharged. If any pressure is noticed as fitting is loosened, allow trapped pressure to bleed off very slowly.

Kinks in the refrigerant tubing or sharp bends will greatly reduce the capacity of the entire system. Use a suitable tube bender when bending the refrigerant lines to avoid kinking.

Use the correct line for the installation you are servicing. Keep the radius of flexible hose bends to ten times the diameter of the hose. Sharper bends will reduce the flow of refrigerant. The flexible hose lines should be routed so they are at least three inches from the exhaust manifold.

O-rings used on tube fittings and unified plumbing plates need to be coated with refrigerant oil prior to installation. Unified plumbing connections with aluminum N-gaskets do not require lubrication before installation.