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AIR CONDITIONING
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6. To complete the charging of the system,
slowly open the LOW side of the manifold
hand valve until the 580 ± 20 gms has been
charged into the system.
7. Perform Cooling System Pressure Test. If
unit Operates satisfactorily, stop engine, shut
stop valves at hose connections to system
and disconnect hoses taking extreme
caution, as the discharge hose can have upto
20.5 kg / cm2 stored in it. Install service valve
caps as required.
WARNING:
Never run compressor without refrigerant in
system as compressor lubricant depends on
refrigerant flow. No sight glass is fitted to the
system due to PAG oil’s foaming properties,
which may be confused with a low gas charge.
Topping up the system is not recommended.
Accurate system refrigerant charge may only be
determined by charging the correct amount of
R134a Pressure gauge readings together with
face air outlet temperatures are the only method
of checking and diagnosing the system cooling
capacity (comparing results with the appropriate
graph)
CHECKING THE SYSTEM OIL CHARGE
The compressor is charged at the factory with
specified 120ml refrigerant oil which circulates
within the entire A.C. system. Only the
recommend oil must be used when adding or
changing oil as specified by A.C. system
suppliers. These oils are not compatible with any
other PAG oil. Mixing of oils of different
manufacturers and different types can result in
glue like substance, failure of lubrication and
seizure of compressor.
Although it is not necessary to regularly check the
oil level within the system, all the A.C. system
components will hold a system of the oil
circulated.
Therefore whenever an A.C. system component
is replaced, a quantity of new refrigerant (PAG)
oil must be added to the system. Where a major
loss of system oil has occurred, due to:
A broken hose or severe leak
Collision damage to refrigerant system
components, or
If excess oil is suspected to be in the system,
then
1. Recover refrigerant from the system, then
remove the compressor
2. Carefully drain the refrigerant oil
3. Flush remaining oil from the rest of the
system using R134a refrigerant.
CAUTION:
A Refrigerant Recovery Unit (RRU) should be
used to flush the system, ensuring that the R134a
is not vented to the atmosphere. The R134a must
be reclaimed via the RRU into a separate bottle.
4. Add recommended quantity of new
refrigerant oil to the compressor.
5. Install the compressor, If ‘O’ ring is damaged
then replace the suction and discharge O-
rings. Ensure O-rings are not twisted and
that the seals and O- rings are clean.
6. Evacuate, and then recharge the system.
7. PAG OIL PRECAUTIONS: DO NOT allow
PAG oil to contact either bare skin or car
paint work. IF CONTACT OCCURS, WASH
OFF PAG OIL IMMEDIATELY.