18
4. Break the vacuum by allowing nitrogen into the port
connections (liquid and gas line pipes) until a positive
pressure is achieved
5. Evacuate the system to a minimum reading of 500
Microns (0.5 Torr).
6. For a moisture-free system, ensure the vacuum is held
without movement for a minimum of 4 hours.
7. If vacuum fails to hold, carry out steps 2 through 6 until
vacuum holds.
Wiring Connections
WARNING
Electric Shock Hazard. Can cause injury or death. Unit
must be rounded in accordance with national and local
codes.
Line voltage is present at all components when unit is
not in operation. Disconnect all remote electric power
supplies before opening access panel. Unit may have
multiple power sources.
CAUTION
All terminal connections must be made as illustrated
in the following diagrams. Improperly connected wiring
could damage unit or cause communication errors
between indoor and outdoor units.
In the U.S.A., wiring must conform with current local codes
and the current National Electric Code (NEC). In Canada,
wiring must conform with current local codes and the
current Canadian Electrical Code (CEC).
Outdoor Unit
• Refer to unit nameplate for minimum circuit ampacity
and maximum over-current protection size
• Make all electrical power wiring connections at the out-
door unit
• Be sure to reattach all electrical box covers after con-
nections are complete
Indoor Unit
• All indoor units are powered by the outdoor unit
• Communication Wiring (Indoor Units 30K and Below):
Use one stranded 4-conductor wire to provide power
and communication
• Communication Wiring (Indoor Units 36K and Above):
Use one stranded 3-conductor wire to provide power
and one stranded 2-conductor wire to provide commu-
nication
• Use minimum of 18 GA stranded wiring
NOTE: When installing a condensate pump the line voltage
will have to be broken by using the condensate
wiring or through the use of an external relay or
contactor
Leak Test and Evacuation
Air and moisture remaining in the refrigerant system will
have undesirable effects as indicated below:
• Pressure in the system rises
• Operating current rises
• Cooling or heating efciency drops
• Moisture in the refrigerant circuit may freeze
• Water may lead to corrosion of parts in the refrigera-
tion system
The line set between the indoor and outdoor units
must be leak tested and evacuated to remove any non-
condensables and moisture from the system.
Leak Test
Use the following procedure to test for system leaks:
1. Connect the manifold gauge set and dry nitrogen gas
cylinder to the suction and gas service ports.
2. Open valve on nitrogen cylinder.
3. Pressurize the system per the pressure test
specications in “Table 5. Pressure Test Specications”.
4. Check that the system pressure remains stable. If
there is any movement check system for leaks.
5. After the system is found to be free of leaks:
• Close valve on nitrogen cylinder
• Relieve the nitrogen pressure by: loosening the
charge hose connector at the nitrogen cylinder
• When the system pressure is reduced to normal,
disconnect the hose from the cylinder
Table 5. Pressure Test Specications
Bar Psig kPa Duration
1 3 44 303 Minimum of 10 minutes
2 15 220 1517 Minimum of 10 minutes
3 32 470 3241 Minimum of 10 minutes
4 45 650 4482
1 hour. Stress test to prove the
integrity of the complete installation.
5 32 470 3241
24 hours. Lower system pressure
test, after conrmation No. 4 was
successfully completed.
IMPORTANT
Use only oxygen-free nitrogen (OFN).
Triple Evacuation Procedure
A Micron or Torr gauge must be used for this procedure.
1. Discharge the oxygen-free nitrogen and evacuate the
system to a reading of 8000 Microns (8 Torr) using all
service valves.
2. Break the vacuum by allowing nitrogen into the port
connections (liquid and gas line pipes) until a positive
pressure is achieved.
3. Evacuate the system to a reading of 5000 Microns (5
Torr).
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