Service and Weigh In Refrigerant for Outdoor Units Delivered Void of Charge
The following procedures are only required if it has been determine that the new outdoor unit is void of charge. Skip to the next section if refrigerant charge is present.
LEAK CHECK, REPAIR AND EVACUATE
If the outdoor unit is void of refrigerant, clean the system using the procedure described below.
1.Leak check system using procedures provided on page 17. Repair any leaks discovered during leak test.
2.Evacuate the system using procedure provided in figure 13.
3.Use nitrogen to break the vacuum and install a new filter drier in the system.
4.Evacuate the system again using procedure in figure 13.
CONNECT MANIFOLD GAUGE SET AND WEIGH−IN CHARGE
After the evacuation procedure, reconnect the manifold gauge set as illustrated in figure 17.
NOTE − Temperature sensor illustrated in figure 17 is not required for initial system weigh in charging.
1.Close manifold gauge set valves and connect the gauge set as exampled in figure 17.
2.Check that fan rotates freely.
3.Inspect all factory− and field−installed wiring for loose connections.
4.Open the high side manifold gauge valve and weigh in liquid refrigerant. Use figure 18 to calculate the correct weigh−in charge.
5.Close manifold gauge valves.
6.Monitor the system to determine the amount of moisture remaining in the oil. It may be necessary to replace the bi−flow filter drier several times to achieve the required dryness level. If system dryness is not verified, the compressor will fail in the future.
7.Continue to Optimizing System Refrigerant Charge on page 24 to optimize the system charge using subcooling method.
MANIFOLD GAUGE SET
GAUGE SET
NOTE Refrigerant
LOW
HIGH
CONNECTIONS FOR OPTIMIZING SYSTEM CHARGE
tank should be turned right−side−up to deliver vapor during charge optimizing procedure.
B
| HFC−410A |
REFRIGERANT |
|
TANK | A |
CHARGE IN | |
LIQUID PHASE |
|
DIGITAL SCALE
TO LIQUID
LINE SERVICEVALVE C
TRUE SUCTION PORT
CONNECTION 
TEMPERATURE
SENSOR
(LIQUID LINE)
D
AClose manifold gauge set valves and connect the center hose to a cylinder of HFC−410A. Set for liquid phase charging.
BConnect the manifold gauge set’s low pressure side to the true suction port.
CConnect the manifold gauge set’s high pressure side to the liquid line service port.
DPosition temperature sensor on liquid line near liquid line service port (use only for subcooling method).
NOTE
the line set is not shown connected to service valves.
Figure 17. Typical Gauge Set Connections for Initial Weight−in Charge or Optimizing System Charge
506728−01 | Page 22 |
