8
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18
62-11389
4 Pressurize the system to 5 to 10 psig (0.3 to 0.7 bar)
with refrigerant at the liquid line service valve.
WARNING
Do not use a nitrogen cylinder without a
pressure regulator. Cylinder pressure is
approximately 2350 psig (159.9 bar). Do not
use oxygen in or near a refrigerant system
as an explosion may occur. (See
Figure 8
−
30)
5 Connect a cylinder of dry nitrogen. Use the dry nitro-
gen to increase the pressure as necessary to 20 to
150 psig (1.4 to 10.2 bar) to detect the leak. The larger
the leak the less pressure is required. The smaller the
leak, the greater pressure is required
6 The recommended procedure for finding leaks from a
system is with an electronic leak detector. Checking
joints with soapsuds is satisfactory only for locating
large leaks, or pinpointing small leaks once a general
area has been located.
7. Once leak checking is complete, remove the refriger-
ant/nitrogen vapor out of the system.
8. If no leaks are found the system is ready for evacu-
ation. (Skip to Step 11)
9. If any leaks are found they must be repaired before
proceeding.
10 Repeat steps 4 thru 9 as necessary.
11. Evacuate the system after all leaks are repaired.
(Refer to Section 8.6.4.)
c. Leak Checking With Low Side Pumped Down
The low side of the system must be leak checked once it
is closed and all repairs complete.
1. Ensure the unit will not start automatically by dis-
abling any two way communication and placing the
Main Power switch in the OFF position. Disconnect
the high voltage source and lockout/tagout the re-
ceptacle.
CAUTION
Only a refrigerant cylinder containing
R404A should be connected to this refriger-
ation unit in order to pressurize the system.
However, dry nitrogen may be used to in-
crease pressure. Any other gas or vapor will
contaminate the system and require addi-
tional removal and evacuation.
2. Connect refrigerant system equipment if not already
connected. Refer to Figure 8
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18
CAUTION
Do not vapor charge R404A. Only liquid
charging through the liquid line service
valve is acceptable.
3. Ensure that the microprocessor MessageCenter dis-
plays “RECOVER/LEAK CHK/EVAC MODE” during
the pressurizing and leak checking procedures. (Re-
fer to Section 5.2.3.) If the microprocessor switches
to charge mode during the process, switch it back to
the “RECOVER/LEAK CHK/EVAC MODE”.
4. Pressurize the low side of the system to 5 to 10 psig
(0.3 to 0.7 bar) with refrigerant from the high side by
turning the liquid line service valve off frontseat for a
few seconds and then returning to frontseat.
WARNING
Do not use a nitrogen cylinder without a
pressure regulator. Cylinder pressure is
approximately 2350 psig (159.9 bar). Do not
use oxygen in or near a refrigerant system
as an explosion may occur. (See
Figure 8
−
30)
5. Connect a cylinder of dry nitrogen. Use the nitrogen to
increase the low side pressure to 20 to 150 psig (1.4
to 10.2 bar) to detect the leak. The larger the leak the
less pressure is required. The smaller the leak, the
greater the pressure required
6. The recommended procedure for finding leaks from a
system is with an electronic leak detector. Checking
joints with soapsuds is satisfactory only for locating
large leaks, or pinpointing small leaks once a general
area has been located.
7. Once leak checking is complete, remove the refriger-
ant/nitrogen vapor from the low side of the system.
8. If no leaks are found the low side of the system is
ready for evacuation. (Skip to Step 11)
9. If any leaks are found they must be repaired before
proceeding.
10. Repeat steps 4 thru 9 as necessary.
11. Disconnect the nitrogen cylinder. Evacuate the low
side of the system after all leaks are repaired. (Refer
to Section 8.6.4.)
d. Leak Checking Compressor
The compressor and its associated switches,
transducers, etc. must be leak checked once the
compressor is closed and all repairs complete.
1. Ensure the unit will not start automatically by dis-
abling any two way communication and placing the
Main Power switch in the OFF position. Disconnect
the high voltage source and lockout/tagout the re-
ceptacle.
2. Connect refrigerant system service equipment to the
suction and discharge service valves, if not already
connected. Refer to Figure 8
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18.
