Leaking Test
Leak test each indoor unit, one unit at a time. Repeat the leak test sequence for each indoor unit.
1. Connect the charging hose of the manifold valve to charge the end of the low-pressure valve.
2. Add dry nitrogen to a pressure of 200 lbs. Tightly close both high- and low-pressure valves.
3. Leak-test flare fittings with soap bubbles. If no leak is detected, release nitrogen.
System Vacuum and Charge
Evacuate each indoor unit, one unit at a time. Repeat the evacuation sequence for each indoor unit.
UNIT DAMAGE HAZARD –
Never use the system compressor as a vacuum pump.
It may result in equipment damage or improper system operation.
Refrigerant pipes and indoor coil should be evacuated using the recommended deep vacuum
method of 500 microns. The alternate triple evacuation method may be used if the procedure
outlined below is followed.
NOTE:
Always break a vacuum with dry nitrogen.
Using Vacuum Pump
1. Completely tighten flare nuts A, B, C, D,
connect manifold gauge charge hose to a
charge port of the low side service valve.
2. Connect charge hose to vacuum pump.
3. Fully open the low side of manifold gauge.
See figure at right.
4. Start vacuum pump.
TESTING AND INSPECTION
Manifold Gauge
Outdoor Unit
Service Valve
500 microns
Low Side Valve
High Side Valve
Charge Hose
Vacuum Pump
Low Side Valve
Charge Hose
Refrigerant
Indoor Unit
Low Side
High Side
WARNING
CAUTION
WARNING
CAUTION
32
