MasterCool 89660 Operating Instructions

OPERATING INSTRUCTIONS
PROFESSIONAL R134a MANIFOLD GAUGE SET
PART #89660
WARNING
Wear Safety Goggles
Avoid Contact with Refrigerant
Ambient Temp (˚F)
65˚
70˚
75˚
80˚
85˚
90˚
95˚
100˚
105˚
TROUBLESHOOTING TIPS
• Low side and high side pressure 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 vibrating gauge needle, usually indicates faulty reed valves in compressor.
• Low side and high side pressures are high.
Usually indicates an over charged system.
HOOK-UP FOR SYSTEM DIAGNOSIS:
• Verify that service ports are clean and free of metal shavings.
• Verify that both valves on the manifold are shut completely.
• Connect blue adapter to low side service port (5).
• Connect red adapter to high side service port (4).
• Start engine. Turn A/C mode selector to HIGH and fan to HIGH.
• Observe pressure on the manifold gauges and refer to your automotive manual for proper diagnosis.
CHARGING REFRIGERANT:
a. Verify that both valves on the manifold are shut completely.
R134a TEMPERATURE PRESSURE CHART
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
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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