Case 845B VHP Operator's Manual page 83

AIR CONDITIONING COMPRESSOR
A/C REfRIGERANT CHARGE (OPTIONAL)
For leak test and/or gas charging use air compressor taps
A and B only.
1. Add 50 grams R134a and allow system to build up 10
bar pressure (145 psi) by applying gaseous nitrogen.
2. Proceed with a gas leak test. Should a leak be CON-
FIRMED, evacuate the system and repair the leak.
Repeat the test.
3. Esvaziar o sistema.
4. Connect he manifold hoses.
5. Connect vacuum pump to manifold center fitting.
6. Open the manifold valves and turn pump on.
7. Allow 20 minutes for pressure gages to indicate 26
inHg vacuum. Close valves and disconnect vacuum.
8. Connect charging cylinder hose, open the manifold
valve high side and apply 1700 grams of gas R134a.
9. Close the manifold valve, remove gas hose and repe-
at the test.
10. Disconnect manifold and install service valve covers.
NOTE: A qualified technician is required to perform A/C
system service.
CHAPTER 3 – INSTRUMENTS AND CONTROLS
RECOMMENDATIONS
1. Turn on A/C only when ventilation is turned on.
2. Make sure the evaporator inlet is not blocked.
3. Should the system performance fall below specifica-
tion, inspect:
System refrigerant pressure;
•
Coolant leaks checking;
•
Operation of fan unit.
•
Evaporator for obstructions.
•
4. Operate A/C at least 10 minutes per week.
5. When engine is at high speed operate fan at maxi-
mum speed.
6. Periodically check external cleaning of condenser (ne-
ver operate condenser if it is 20% blocked or more).
7. Close all doors and windows when operating the A/C.
8. For fast cooling, use cabin internal air recirculation
control.
SYSTEM MAINTENANCE
1. Perform the check for leaks every 6 months of ope-
ration.
2. At every component replacement or R134a refrigerant
leak, complete the oil level through the compressor with
approximately 50 ml of PAG oil (Polyalkylene Glycol). If
the component replaced is the compressor there is no
need to complete the oil level, as the new compressor
is already supplied with oil.
3. Clean condenser monthly or whenever the condenser
air inlet shows 20% obstruction.
4. Check screw torque and belt tensioning yearly.
5. Clean air conditioning filter monthly or whenever air
flow reduction is noticed.
6. In case of undesirable odors in the air conditioning sys-
tem, operate the system for a few minutes, by putting
the ventilation speed selector at maximum position and
turning the temperature control selector totally clockwi-
se (HOT).
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