Important Notes - MasterCool 99860-A Operating Instructions Manual

• Press ENTER once desired manufacturer is found.
• Press VEHICLE
VEHICLE or
• Once you have found the desired model/year, you can change the units of measure by
pressing the UNITS button. Scroll through your options of LBS/OZ, LBS/ML, KG/OZ, KG/ML .
• Press ENTER once desired model, year and measurement is found.
• Refrigerant & Oil Capacity measurements will display at the top of the LCD screen.
• Press ENTER again to begin pressure readings.
PRE-SERVICE INSTRUCTIONS
1. Close both valves on the manifold gauge set by turning the High and Low knobs clockwise.
2. Attach the High and Low couplers to the Red and Blue hoses.
If using manual couplers, open the plunger by turning the knob counter-clockwise prior
to connection to the system. (fig. A)
3. Connect the Red hose to the High port and the Blue hose to the Low port on the manifold
gauge.
HOOK-UP FOR SYSTEM DIAGNOSIS
To properly diagnose the problem in the A/C system, first check the system's overall perfor-
mance. This includes testing the system's pressure and refrigerant flow. The system pressure can
be checked with the manifold gauge set.
NOTE: Be sure that the hand valves on the manifold gauge set are in the closed position.
Always wear gloves and safety goggles when working with refrigerant.
1. Remove the protective caps from the system ports. Check for leaks at the ports.
2. Connect the Low side service hose (Blue) to the suction side of the compressor. Connect
the High side service hose (Red) to the discharge side of the compressor. Make sure the
couplers are securely snapped.
3. If using manual couplers, move the plunger down within the coupler by turning the knob
clockwise in order to open the port valves and start refrigerant flow.
MANUAL COUPLER (FIG. A)
To attach to the system, retract the plunger by turning the knob
fully counter-clockwise. Connect to the system by lifting up the
sleeve, placing the service port inside the coupler and releasing to
lock. To start the flow, turn the knob fully clockwise (opening the
service port).

IMPORTANT NOTES

A system that has been opened or one that is found to be excessively low on refrigerant pressure
as a result of a leak, must be fully evacuated by means of recycling and deep vacuum.
A system that has been evacuated must be repaired, leak tested and evacuated before charging.
If charging on the liquid or High side, use only the High side valve on the manifold 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/recycling machine to evacuate any
refrigerant remaining in the hoses.
R134a
Ref .Cap . :2.70 OIL.Cap . :11.00
LBS
BAR PSIN-Hg MPa Kg/cm 2 BAR PSI
Low High
VEHICLE VEHICLE
POWER ENTER
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˚
to scroll through each model/year. For faster scrolling, press and hold
(If you pass the model/year you desire use the
oz
MPa Kg/cm 2
Condenser
UNITS
PATENT
PENDING
High
Low
Compressor
High and Low service port locations may vary.
R134a TEMPERATURE PRESSURE CHART
www.mastercool.com
Low Side Gauge
25-35 psi
35-40 psi
35-45 psi
40-50 psi
button to go back.)
Evaporator
Receiver
High Side Gauge
135-155 psi
145-160 psi
150-170 psi
175-210 psi
SLEEVE
3