Leak Checking; Adding A Complete Charge; Leak Checking A Charged System; Leak Checking A System Without Charge - Carrier VECTOR 6500 Operation & Service Manual

3 If charge is to be added: place cylinder of refrigerant
on a scale and connect a charging line and gauge
from cylinder to liquid line service valve. Start unit in
Continuous Operation with a set point lower than re-
frigerated compartment temperature. Wait until unit
switches to high speed operation. Run approximately
ten minutes.
4 Note weight of cylinder and refrigerant.
5 Frontseat the liquid line service valve (turn clockwise)
and watch the pressure on the manifold gauge. When
the pressure falls below the pressure in the refriger-
ant cylinder [or to 50 psig (3.4 bar)], open the cylinder
valve and monitor the liquid refrigerant to flow into the
unit.
6 When approximately 5 lbs. (2.3 kg) have been added,
close the cylinder valve, and backseat the liquid line
service valve.
7 Recheck for the correct refrigerant charge. (Refer to
preceding step a.) Repeat preceding steps as re-
quired. When charge level adjustment is complete,
remove refrigerant service equipment.
g. Adding a Complete Charge
1 Evacuate unit and leave in deep vacuum. (Refer to
Section 8.6.4.)
2 Determine charge required for this unit (refer to the
model/serial number nameplate or Table 2-1) and
procure a refrigerant cylinder with sufficient weight of
refrigerant. Place cylinder on scale and connect
charging line from cylinder to liquid line service valve.
3 Note weight of cylinder and refrigerant.
4 Open liquid valve on cylinder. Midseat liquid line ser-
vice valve and allow the liquid refrigerant to flow into
the unit until the correct weight of refrigerant has been
added.
NOTE
It is possible that all liquid may not be pulled into
the receiver, as outlined in step 4. In this case,
add the additional refrigerant in accordance
with the charge adjustment procedures, refer to
preceding step f.
5 When scale indicates that the correct charge has
been added, close liquid line valve on cylinder and
backseat the liquid line service valve. Remove charg-
ing hose.

8.6.3 Leak Checking

The condition that the system may be in when leak
checking is required include; when the system is
charged, when the system is without charge, when the
low side has been pumped down and when only the
compressor is to be leak checked. Procedures for each
condition are provided in the following subsections.
a. Leak Checking a Charged System
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.
Service Mode is not required for this procedure.
2. Verify that the suspected leak area (high or low side)
has sufficient pressure [minimum 20 psig (1.4 bar)] to
detect the leak. The larger the leak the less pressure
is required. The smaller the leak, the greater the pres-
sure required.
3. 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.
4. Some leaks may be repaired by simply tightening a
connection. Others may require removal of the
charge, refer to Section 8.6.2.
5. Check for proper unit operation by running Pretrip
(Refer to Section 3.4).
b. Leak Checking a System Without Charge
The refrigeration 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.
2. Connect refrigerant system equipment if not already
connected. Refer to Figure 8−18
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.
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".
8−17
NOTE
CAUTION
CAUTION
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