AEC ACOA Series Air-Cooled Central Chillers - Manual (Page 51)

Symptom Possible cause Solution
Compressor cycles on low
pressure control. Improper water flow. Check pressure drop across
evaporator for proper flow.
Fouled evaporator. Backflush and/or clean.
Compressor cycles off on
high pressure control. Compressor discharge valve
partially closed. Open valve fully and close with
one turn.
Air in system. Purge condenser coils.
Overcharge of refrigerant. Reclaim system while in
operation until bubbles show in
sight glass. Close valve and
add small amount of
refrigerant until sight glass just
clears.
High pressure control
improperly set. Adjust the control.
Condenser fan inoperative. Check, replace or repair set
screw (pulley), fan motor, or
inoperative fan control.
Dirty condenser. Clean condenser surfaces with
brush and/or vacuum.
Fan cycle switches
inoperative or set too high. Check and readjust.
Fan motors not running. Check contactor, check motor,
check capacitor (if single
phase).
Fan motor reverse rotation. Reverse two fan motor leads
(three-phase only).
Figure 21
ACOA Load Points
ACOA Isolator weights Oper.
model Dimensions (inches) Load by position (lbs.) weight
number A B C D E #1 #2 #3 #4 #5 #6 #7 #8 lbs.
ACOA15 19.0” 83.0” 37.3 543 378 572 372 1,865
ACOA20 19.0” 83.0” 37.3 595 421 606 395 2,107
ACOA25 19.0” 83.0” 37.3 651 471 653 433 2,208
ACOA30 19.0” 69.0” 119.0” 37.3 597 487 298 608 476 281 2,747
ACOA35 19.0” 69.0” 119.0” 37.3 640 525 309 638 498 285 2,895
ACOA45 19.0” 83.0” 80.3” 1,025 867 1,140 997 4,029
ACOA55 19.0” 69.0” 119.0” 80.3” 974 780 341 1,045 1,047 554 4,741
ACOA70 19.7” 69.0” 119.0” 80.3” 1,024 952 593 1,112 1,103 608 5,392
ACOA80 12.0” 92.0” 172.0” 83.0” 1,340 1,514 715 1,340 1,514 715 7,138
ACOA90 12.0” 92.0” 172.0” 252.0” 83.0” 1,242 1,562 480 308 1,295 1,868 1,064 618 8,437
ACOA100 12.0” 92.0” 172.0” 252.0” 83.0” 1,289 1,647 516 309 1,348 1,972 1,106 620 8,807
ACOA110 12.0” 92.0” 172.0” 252.0” 83.0” 1,234 1,814 974 438 1,268 1,855 1,313 751 9,647
ACOA125 12.0” 92.0” 172.0” 252.0” 83.0” 1,273 1,844 1,330 758 1,273 1,844 1,330 758 10,410
ACOA135 12.0” 92.0” 172.0” 252.0” 83.0” 1,321 2,032 1,539 844 1,321 2,032 1,539 844 11,472
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ACOA Series Air-Cooled Central Chillers