MasterCool R134a Instruction Manual page 3

gauge set. Make sure the low side valve is closed. After charging, test the system by
turning on the engine and running the A/C with both valves closed on the manifold. After
testing, disconnect the couplers from the system and make sure to use a recovery/recy-
cling machine to evacuate any refrigerant remaining in the hoses.
R134a
Ref .Cap . :2.70
LBS
BAR PSIN-Hg MPa Kg/cm 2
Low
VEHICLE VEHICLE
POWER
DIAGNOSING TIPS FOR THE A/C SYSTEM
• Low side and high side pressures are low. Usually indicates a low charge.
• Low side pressure is low and high side pressure is high. Usually indicates a blockage in
the system. (i.e. expansion of valve or orifice tube.)
• Low side pressure is high and high side pressure is low. When accompanied by a
fluctuating digital reading, usually indicates faulty reed valves in compressor.
• Low side and high side pressures are high. Usually indicates an over charged system.
Ambient Temperature (˚F)
65˚
70˚
75˚
80˚
85˚
90˚
95˚
100˚
105˚
CHARGING REFRIGERANT
A. Verify that both valves on the manifold are shut completely.
B. Turn on car and A/C system (this will aid in charging of the refrigerant.)
C. Connect the other end of the yellow hose to refrigerant gas supply.
(Follow refrigerant manufacturer's instructions for proper dispensing.)
D. Open manifold low side (blue) valve slowly until pressure reaches 40 psi. Do no exceed
40 psi during recharging process. Exceeding 40 psi could damage the compressor.
E. When charging is finished, close low side (blue) valve.
EVACUATION OF SYSTEM WITH VACUUM PUMP AND LEAK TESTING
A. Verify that there is no refrigerant in the A/C system.
B. Attach blue and red adapters to A/C system.
C. Connect yellow hose to vacuum pump, turn on pump.
D. Open manifold low side (blue) valve.
E. Open manifold high side (red) valve.
*After system has been evacuated to a gauge reading of 29 IN-Hg (inches of
vacuum), run vacuum pump for 20 minutes.
F. Close both high and low side manifold valves.
G. Allow system to sit and check gauges to verify vacuum remains.
TROUBLESHOOTING:
Low Battery Indicator:
A special icon will appear in the lower right hand corner of the LCD
+ -
when the battery must be replaced.
No Display:
Check the battery and polarity.
OIL.Cap . :11.00
oz
BAR PSI MPa Kg/cm 2
High
ENTER
UNITS
PATENT
PENDING
High
Low
High and Low service port locations may vary.
R134a TEMPERATURE PRESSURE CHART
Condenser
Compressor
Low Side Gauge
25-35 psi
35-40 psi
35-45 psi
40-50 psi
45-55 psi
45-55 psi
50-55 psi
50-55 psi
50-55 psi
Evaporator
Receiver
High Side Gauge
135-155 psi
145-160 psi
150-170 psi
175-210 psi
225-250 psi
250-270 psi
275-300 psi
315-325 psi
340-345 psi
3