Johnson Controls York YIA Series, Схема подключения

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JOHNSON CONTROLS
FORM 155.21-W2 (1209)
LD06829
FIG. 14 – MULTIPLE UNITS (TWO) – PARALLEL
OPERATION – INDIVIDUAL UNIT PUMPS
(COOLING APPLICATION ONLY)
MULTIPLE UNITS (TWO) – PARALLEL
OPERATION – INDIVIDUAL UNIT PUMPS
This piping arrangement is the same as Fig . 15, ex ‑
cept that the chilled water pumps associated with each
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 . 12) the temperature of the supply chilled
water does not change.
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 . 12), mixed chilled water
tempera ture will rise as a result of uncooled return water
flowing through the inoperative unit. For individual unit
chilled water pump piping, refer to Fig . 14.
FIG. 15 –
MULTIPLE UNITS (TWO) – PARALLEL
OPERATION – SINGLE CHILLED WATER
PUMP (COOLING APPLICATION ONLY)
LD06830
EVAPORATOR
EVAPORATOR
EVAPORATOR
EVAPORATOR