SECTION 22: HEATING AND AIR CONDITIONING
DOB 2490-2789 | X3-45 Commuter PA1605 Maintenance Manual (Final Version – Rev.2 April 2016)
19
It is a good practice to replace the cap after
each use of the cylinder for the same reason. If
the cylinder is exposed to the sun’s radiant heat
pressure increase resulting may cause release
of the safety plug or the cylinder may burst.
For the same reason, the refrigerant cylinder
should never be subjected to excessive
temperature when charging a system. The
refrigerant cylinder should be heated for
charging purposes by placing it in 125
o
F (52
o
C)
water. Never heat above 125
o
F (52
o
C) or use a
blowtorch, radiator, or stove to heat the cylinder.
Welding or steam cleaning on or near any
refrigerant line or components of the A/C system
could build up dangerous and damaging
pressures in the system.
If a small cylinder is ever filled from a large one,
never fill the cylinder completely. Space should
always be allowed above the liquid for
expansion. Weighing cylinders before and
during the transfer will determine the fullness of
the cylinders.
WARNING
One of the most important precautions when
handling refrigerant consists in protecting the
eyes. Any liquid refrigerant which may
accidentally escape is approximately -40
o
F (-
40
o
C). If refrigerant comes in contact with the
eyes, serious injury could result. Always wear
goggles to protect the eyes when opening
refrigerant connections.
6.2.3 Treatment in Case of Injury
If liquid refrigerant comes in contact with the
skin, treat the injury as if the skin was frost-bitten
or frozen. If liquid refrigerant comes in contact
with the eyes, consult an eye specialist or doctor
immediately. Give the following first aid
treatment:
1. Do not rub the eyes. Splash eyes with cold
water to gradually bring the temperature
above the freezing point.
2. Apply drops of sterile mineral oil (obtainable
at any drugstore) in the eyes to reduce the
possibility of infection. The mineral oil will
also help in absorbing the refrigerant.
6.2.4 Precautions in Handling Refrigerant
Lines
1. All metal tubing lines should be free of
kinks, because of the resulting restrictions
on the flow of refrigerant. A single kink can
greatly reduce the refrigeration capacity of
the entire system.
2. The flexible hose lines should never be
allowed to come within a distance of 2-½"
(6,3 cm) from the exhaust manifold.
3. Use only sealed lines from parts stock.
4. When disconnecting any fitting in the
refrigeration system, the system must first
be discharged of all refrigerant. However,
proceed very cautiously, regardless of
gauge readings. If liquid refrigerant happens
to be in the line, disconnect fittings very
slowly, keeping face and hands away so
that no injury can occur. If pressure is
noticed when fitting is loosened, allow it to
bleed off very slowly.
WARNING
Always wear safety goggles and gloves when
opening refrigerant lines.
5. Any line is opened to the atmosphere should
be immediately capped to prevent entrance
of moisture and dirt.
6. The use of the proper wrenches when
making connections on O-ring fittings is
important. The use of improper wrenches
may damage the connection. The opposing
fitting should always be backed up with a
wrench to prevent distortion of connection
lines or components. When connecting the
flexible hose connections, it is important
that the swaged fitting and the flare nut, as
well as the coupling to which it is attached,
be held at the same time using three
different wrenches to prevent turning the
fitting and damaging the ground seat.
7. The O-rings and seats must be in perfect
condition. The slightest burr or piece of dirt
may cause a leak.
8.
O-rings and gaskets should be coated
with refrigeration oil
and installed on the
line before the line is inserted into the fitting
to prevent damaging the O-ring. If leaks are
encountered at the couplings or connectors,
