NOTE: R–12 refrigerant is a chlorofluorocarbon which
when released in the atmosphere can contribute to the depletion of the ozone
layer in the upper atmosphere. Ozone filters out harmful radiation from the
sun. Be sure to consult the laws in your area before servicing the air conditioning
system. In some states it is illegal to preform repairs involving refrigerant
unless the work is done by a certified technician.
Because of the the inherent dangers involved with working on air conditioning
systems and R–12 refrigerant, the following safety precautions must be
strictly adhered to in order to service the system safely.
- Avoid contact with a charged refrigeration system, even when working on
another part of the air conditioning system or vehicle. If a heavy tool comes
into contact with a section of tubing, or a heat exchanger, it can cause the
relatively soft material to rupture.
- When it is necessary to apply force to a fitting which contains refrigerant,
as when checking that all system couplings are securely tightened, use a wrench
on both parts of the fitting involved, if possible. This will avoid putting
torque on the refrigerant tubing. (It is advisable, when possible, to use
line wrenches when tightening these flare nut fittings.)
- Do not attempt to discharge the system by merely loosening a filter, or
removing the service valve caps and opening these valves. Precise control
is possible only when using a proper A/C refrigerant recovery station. Wear
protective gloves when connecting or disconnecting service gauge hoses.
- Never start a system without first verifying that both service valves are
properly installed, and that all fittings throughout the system are snugly
connected.
- Avoid applying heat to any refrigerant line or storage vessel. Never allow
a refrigerant storage container to sit out in the sun, or any other sources
of heat, such as a radiator.
- Always wear goggles to protect your eyes when working on a system. If refrigerant
contacts the eyes, it is advisable in all cases to see a physician as soon
as possible.
- Frostbite from liquid refrigerant should be treated by first gradually warming
the area with cool water, and then gently applying petroleum jelly. A physician
should be consulted.
- Always keep refrigerant drum fittings capped when not in use. If the container
is equipped with a safety cap to protect the valve, make sure the cap is in
place when the can is not being used. Avoid sudden shock to the drum, which
might occur from dropping it, or from banging a heavy tool against it. Never
carry a drum in the passenger compartment of a car.
- Always completely discharge the system into a suitable recovery unit before
painting the vehicle (if the paint is to be baked on), or before welding anywhere
near refrigerant lines.
- When servicing the system, minimize the time that any refrigerant line is
open to the air, in order to prevent dirt and moisture entering the system.
Always replace O-rings on lines or fittings which are disconnected. Prior
to installation coat, but do not soak, replacement O-rings with suitable compressor
oil.
