13
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 efficiency 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
specifications in “Table 7. Pressure Test
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 7.
Pressure Test Specifications
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 confirmation 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 oxygenfree 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).
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 moisturefree 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
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).
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.
Outdoor Unit
• Refer to unit nameplate for minimum circuit ampacity
and maximum over-current protection size.
• Make all electrical power wiring connections at the
outdoor unit.
•
Be sure to reattach all electrical box covers after con
nections are complete.
Indoor Unit
• Indoor unit is powered by the outdoor unit.
•
Communication, power and ground wiring - Use one
stranded 3conductor with ground wire.
•
See “Table 8. Single Zone Installation Electrical” on
page 14 for wiring requirements.
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.
IMPORTANT
All illustrations listed are typical wiring diagrams. Refer
to the wiring diagram on the unit for actual wiring.
