Chiller Shipped With Holding Charge - Carrier AquaEdge 23XRV Start-Up, Operation And Maintenance Instructions Manual

COOLER
FRAME SIZE LENGTH
FT (M)
12
(3.6)
3
14
(4.3)
12
(3.6)
4
14
(4.3)
12
(3.6)
5
14
(4.3)
FRAME SIZE
A1
A2
A3
A4
A5
A6
B1
B2
B3
B4
B5
B6
CHILLER SHIPPED WITH HOLDING CHARGE — Use the
CONTROL TEST TERMINATE LOCKOUT function to
monitor conditions and start the pumps.
If the chiller has been shipped with a holding charge, the
refrigerant is added through the refrigerant charging valve
(Fig. 40-43, valves 1a and 1b) or to the pumpout charging con-
nection. First evacuate the nitrogen holding charge from the
chiller vessels. Charge the refrigerant as a gas until the system
pressure exceeds 35 psig (141 kPa) for HFC-134a. After the
chiller is beyond this pressure the refrigerant should be charged
as a liquid until all the recommended refrigerant charge has
been added.
TRIMMING REFRIGERANT CHARGE — T h e 2 3 X R V
chiller is shipped with the correct charge for the design duty of
the chiller. The LTD (leaving temperature difference) between
the EVAP REFRIG LIQUID TEMP and LEAVING CHILLED
LIQUID can be checked against the design conditions to con-
firm that the charge is correct. In the case where leaks have
been found and corrected and the LTD is greater than about
4° F (2.2° C) above design, add refrigerant until the full load
design LTD is approached. (A high cooler LTD can also be
caused by dirty tubes, water box division plate bypass, a par-
tially closed liquid isolation valve, or the float valve.)
Table 16 — Refrigerant Charges, Frame Sizes 3-5
COOLER
CODE
lb (± 25 lb)
30
31
32
35
36
37
40
41
42
45
46
47
50
51
52
55
56
57
Table 17 — Refrigerant Charges, Frame Sizes A,B
COOLER LENGTH
FT (M)
lb (± 25 lb)
12
(3.6)
14
(4.3)
CHARGE AMOUNT (R-134a)
WITH ECONOMIZER
kg (± 11 kg)
800 363
800 363
800 363
910 413
910 413
910 413
900 408
900 408
900 408
1015 460
1015 460
1015 460
1250 567
1250 567
1250 567
1430 649
1430 649
1430 649
CHARGE AMOUNT (R-134a)
WITH ECONOMIZER
kg (± 11 kg)
840 381
860 390
880 399
900 408
930 422
960 435
950 431
970 440
1000 454
1020 463
1060 481
1090 494
Trimming the charge can best be accomplished when the
design load is available. The calibration of the EVAP REFRIG
LIQUID TEMP and LEAVING CHILLED LIQUID tempera-
ture sensors should be confirmed prior to checking for proper
cooler LTD. Compare the difference between EVAP REFRIG
LIQUID TEMP and LEAVING CHILLED LIQUID tempera-
tures to the chiller design conditions. Add or remove refriger-
ant, if necessary, to bring the cooler leaving temperature
difference to design conditions or within minimum differential.
Check for low load oil recovery after making adjustments to
the refrigerant charge. The bubbling mixture of refrigerant and
oil mixture should be visible through the vaporizer sight glass
at low load when the oil reclaim valve is open. If a bubbling
mixture is not observed when the oil reclaim valve is open, add
refrigerant.
The preferred location at which refrigerant should be added
directly into the chiller is through the service valves on top of
the cooler condenser. if these valves are not accessible due to
presence of an attached pumpdown unit which does not have a
storage tank, slowly add charge through the valve connected to
the side of the condenser drain float sump. Adding charge
through the cooler refrigerant pumpout valve at the base of the
cooler (off the liquid line) may force debris into the condenser
float valve and is not recommended.
81
WITHOUT ECONOMIZER
lb (± 25 lb) kg (± 11 kg)
650 295
650 295
650 295
760 345
760 345
760 345
750 340
750 340
750 340
865 392
865 392
865 392
1100 499
1100 499
1100 499
1280 581
1280 581
1280 581
WITHOUT ECONOMIZER
lb (± 25 lb) kg (± 11 kg)
820 372
840 381
860 390
880 399
910 413
940 426
930 422
950 431
980 445
1000 454
1040 472
1070 485