Komatsu 830E-AC Shop Manual page 940

SYSTEM SERVICING
Servicing an air conditioning system really means
closely monitoring refrigerant flow. For this reason,
the following procedures deal extensively with the
proper use, handling, care and safety factors
involved in the R-134a refrigerant quality and quan-
tity in an air conditioning system.
Because the refrigerant in an air conditioning system
must remain pressurized and sealed within the unit to
function properly, safety is a major consideration
when anything causes this pressurized, sealed con-
dition to change. The following warnings are pro-
vided here to alert service personnel to their
importance before learning the correct procedures.
Read, remember, and observe each warning before
beginning actual system servicing.
NOTE: If the mine operates a fleet with some trucks
using R-12 and others using R-134a refrigerant, it is
essential that servicing tools that come into contact
with the refrigerant (gauge sets, charging equipment,
recycle/recovery equipment etc.) be dedicated to one
type refrigerant only, to prevent cross contamination.
.
Federal regulations prohibit venting R-12 and
R134a refrigerant into the atmosphere. An SAE
and UL approved recovery/recycle station must
be used to remove refrigerant from the A/C sys-
tem. Refrigerant is stored in a container on the
unit for recycling, reclaiming, or transporting. In
addition, technicians servicing A/C systems
must be certified they have been properly trained
to service the system.
Although accidental release of refrigerant is a
remote possibility when proper procedures are
followed, the following
observed when servicing A/C systems:
Provide appropriate protection for your eyes
(goggles or face shield) when working around
refrigerant.
A drop of the liquid refrigerant on your skin will
produce frostbite. Wear gloves and exercise
extreme care when handling refrigerant.
If even the slightest trace of refrigerant enters in
your eye, flood the eye immediately with cool
water and seek medical attention as soon as pos-
sible.
N4-14
warnings must be
Operator Comfort
Ensure sufficient ventilation whenever refriger-
ant is being discharged from a system, keeping
in mind refrigerant is heavier than air and will fall
to low-lying areas.
When exposed to flames or sparks, the compo-
nents of refrigerant change and become deadly
phosgene gas. This poison gas will damage the
respiratory system if inhaled. NEVER smoke in
an area where refrigerant is used or stored.
Never direct a steam cleaning hose or torch in
direct contact with components in the air condi-
tioning system. Localized heat can raise the
pressure to a dangerous level.
Do not heat or store refrigerant containers above
49° C (120° F).
Do not flush or pressure test the system using
shop air or another compressed air source. Cer-
tain mixtures of air and R-134a refrigerant are
combustible when slightly pressurized. Shop air
supplies also contain moisture and other con-
taminants that could damage system compo-
nents.
Trucks operating in cold weather climates must
continue to keep the A/C system charged during
cold weather months. Keeping the system
charged helps prevent moisture intrusion into
system oil and desiccants.
10/06 N04031