ZEST BOLT Service Manual

AIR CONDITIONING 34 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.