Carrier NDK33BN0KB, Руководство по эксплуатации и обслуживанию

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62-61753-21 8-16
This operation is to test the evacuation setup for
leaks, repair if necessary.
d. Open the economizer service line valve and midseat
the refrigerant system service valves. Ensure
the microprocessor
message center reads
"RECOVER/LEAK CHK/EVAC MODE" (refer to
section 5.1.3).
e. Then open the vacuum pump and electronic vacu-
um gauge valves, if they are not already open. Start
the vacuum pump. Evacuate unit until the electronic
vacuum gauge indicates 2000 microns. Close the
electronic vacuum gauge and vacuum pump valves.
Shut off the vacuum pump. Wait a few minutes to be
sure the vacuum holds.
f. Break the vacuum with dry nitrogen. Raise system
pressure to approximately 0.1 bar (2 PSIG). En-
sure the microprocessor does not switch to the
charge mode. If this occurs, switch it back to the
"RECOVER/LEAK CHK/EVAC MODE" (refer to
section 5.1.3).
g. Purge nitrogen from system.
h. Repeat steps e through g one time.
i. Evacuate unit to 500 microns. Close off vacuum
pump valve and stop pump. Wait five minutes to see
if vacuum holds. This checks for residual moisture
and/or leaks.
j. With a vacuum still in the unit, the refrigerant charge
may be drawn into the system from a refrigerant
container on weight scales. The correct amount of
refrigerant may be added by observing the scales.
Correct charge will be found in Table 2-1.
8.5.5 Adding Refrigerant To System
CAUTION
Do not vapor charge R-404A or R-452A.
Only liquid charging is acceptable.
Adding a Full Charge
a. Dehydrate unit and leave in deep vacuum. (Refer to
section 8.5.4).
b. Place drum of refrigerant on scale and connect
charging line from drum to liquid line service valve.
Purge charging line at outlet valve.
c. Note weight of drum and refrigerant.
d. Open liquid valve on drum. Open liquid line service
valve half way and allow the liquid refrigerant to flow
into the unit until the correct weight of refrigerant
has been added as indicated by scales. Correct
charge will be found in Table 2-1.
NOTE
It is possible that all liquid may not be pulled
into the receiver, as outlined in step d. In this
case, frontseat the liquid line service valve and
run the unit in cooling until the correct amount
of refrigerant is added.
e. When scale indicates that the correct charge has
been added, close liquid line valve on drum and
backseat the liquid line service valve.
f. Start unit in cooling mode. Run approximately ten
minutes. Partially block off air flow to condenser coil
so discharge pressure rises to 15.8 bar (230 psig).
Refrigerant should appear at center line of lower re-
ceiver sight glass.