YORK INTERNATIONAL
8
LD06829
FIG. 12 – MULTIPLE UNITS (TWO) – PARALLEL
OPERATION – INDIVIDUAL UNIT PUMPS
FIG. 12 – MULTIPLE UNITS (TWO) – PARALLEL
OPERATION – INDIVIDUAL UNIT PUMPS
This piping arrangement is the same as Fig. 13, except
that the chilled water pumps associated with each cooler
(evaporator) are cycled on and off with the unit. This
results in reduced chilled water flow rates whenever a
single unit can handle the cooling load. Because no
chilled water flows through the inoperative unit, the
mixed water temperature peculiar to using a single pump
is avoided. When one unit is cut-out by the sequence
control (Fig. 10) the temperature of the supply chilled
water does not change.
FIG. 13 – MULTIPLE UNITS (TWO) – PARALLEL
OPERATION – SINGLE CHILLED WATER PUMP
For this piping arrangement, each chiller’s water sensor
is located in its own leaving water nozzle. This produces
a constant “mixed” chilled water temperature when both
units are operating. When either unit is cycled off by
the sequence control (Fig. 10), mixed chilled water
temperature will rise as a result of uncooled return wa-
ter flowing through the inoperative unit. For individual
unit chilled water pump piping, refer to Fig. 12.
FIG. 13 – MULTIPLE UNITS (TWO) – PARALLEL
OPERATION – SINGLE CHILLED WATER
PUMP
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FIG. 14A – ELECTRO-MECHANICAL STARTER
MANUAL RESET OVERLOADS (2300 TO
4160 VOLTS U.L. OR C.S.A. APPROVED
UNITS ONLY) CHILLERS EQUIPPED
WITH “P” COMPRESSORS
FIG. 14 – ELECTRO-MECHANICAL STARTER MANUAL
RESET OVERLOADS (2300 TO 4160 VOLTS
U.L. OR C.S.A. APPROVED UNITS ONLY)
ALL CHILLERS EXCEPT THOSE EQUIPPED
WITH “P” COMPRESSORS
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