FORM 160.54-PW7
7
YORK INTERNATIONAL
FIG. 11 – MULTIPLE UNITS (TWO) - SERIES OPERATION
The supply chilled water temperature to the building is
normally determined by the “chilled liquid temp.”
setpoint for Unit #2. When lead selector position of
LD06826
FIG. 11 – MULTIPLE UNITS (TWO) – SERIES OPERATION (NOTES 8 & 11)
sequence control kit (Fig. 10) is Unit #1, the supply chilled
water temperature to the building will be the tempera-
ture control setpoint on Unit #1 OptiView Control Cen-
ter. If lower temperature is desired, reprogram the
“chilled liquid temp.” setpoint for Unit #1.
LD06835
FIG. 10 – TWO UNIT SEQUENCE CONTROL
FIG. 10 – TWO UNIT SEQUENCE CONTROL
Provides that cycling thermostat RWT will automati-
cally cycle either #1 or #2 unit. Timer 3TR is an addi-
tional feature which prevents simultaneous starting of
lead and lag unit following a power failure and elimi-
nates nuisance starting of lag unit due to periodic fluc-
tuations in temperature. For two unit sequence control
kit, order YORK Accessory Kit No. 466-61597T for
controls as specified with NEMA 1 enclosure.
RWT has 20°F to 80°F range with adjustable differen-
tial of 3-1/2 to 14°F; 6 ft. of capillary with 3/8" x 5"
bulb and 1/2" NPT brass well (maximum liquid DWP
300 PSIG). The thermostat is drawn to indicate its op-
eration closes on rise. A 1/2" pipe coupling in the re-
turn chilled water line from the building must be fur-
nished (by others) for RWT control well.