Vinotemp VC7S - SERVICE PRECAUTIONS FOR R600 A SYSTEM

3.4 SERVICE PRECAUTIONS FOR R600A SYSTEM
Features of refrigerant (R600a)
 Achromatic and odor less gas.
 Flammable gas and the ignition (explosion) at 494°C.
 Upper/lower explosion limit: 1.8%~8.4%/Vol.
Features of the R600a refrigeration unit
 Charging of around 60% refrigerant compared with a R134a model
 The suction pressure is below 1bar (abs) during the operation.
 Because of its low suction pressure, the external air may flow in the cycle system when the
refrigerant leaks, and it causes malfunction in the compressor.
 The displacement of compressor using R600a must be at least 1.7 times larger than that of
R134a.
 Any type of dryer is applicable (XH-5, 7, 9).
 The EVAPORATOR or any other cycle part that has welding joint is hidden in the foam. (If not
hidden inside, the whole electric parts must be tested with the LEAKAGE TEST according to
the IEC Standard.)
 The compressor has label of the refrigerant R600a.
 Only the SVC man must have an access to the system.
Installation place
 Must be well ventilated.
 Must be 20 m3 or larger.
 Must be no-smoking area.
 No ignitable factors must be present.
Utilities
 Refrigerant cylinder (MAX NET 300g)
 Manometer
 Vacuum pump (600L/min)
 Piercing Clamp
 Quick coupler • Hoses (5m-1EA, 1m-3EA)
 LOKRING
 Portable Leakage detector (3g/year)
 Nitrogen cylinder (for leakage test)
 Concentration gauge
Make sure before Servicing
 Refrigerant Confirm: the refrigerant by checking Name Plate and the label on the compressor,
after opening the COVER ASSY, BACK-M/C.
 If the refrigerant is R600a, you must not weld or apply a heat source.
Air Recharging in Compressor
Before refilling the refrigerant, you must perform the test according to “TROUBLESHOOTING
GUIDE”. When the defects are found, you must discharge the residual refrigerant (R600a) in the
outdoor. For discharging the refrigerant R600a, break the narrow portion of tube extension by
hand or with a pipe cutter. Leave it for
30min in outside to stabilize the pressure
with ambient. Then, check the pressure by
piercing the filter dryer part with piercing
pliers. If the refrigerant is not completely
discharged, let the refrigerator alone for
more 30min in outside.
Attach the service tube installed with a
Schrader valve (one-way valve). Then, connect the Schrader valve (one-way valve) to the pump