YORK INTERNATIONAL
100
FORM 150.62-NM7 (103)
Unit Controls
Program
The superheat setpoint is programmable under the
Pro gram key. Superheat may be programmed for 10°F
to 15°F, (-12.2°C to -9.4°C) with 12°F (-11.1°C) as the
default. It is recommended that a 12°F to 15°F (-12.2°C
to -9.4°C) setpoint be used for most applications.
Safeties
Two safeties are associated with the EEV, the low su-
per heat safety and the sensor fault safety. Details are
outlined in the System Safeties section.
CONDENSER FAN CONTROL
(YCAL0043 – YCAL0253 CHILLERS)
Condenser fan operation must be programmed with the
Options key under “Fan Control.” Condenser fan con trol
can be selected for Ambient Temp. and Disch. Pres sure,
or Discharge Pressure Only.
The condenser fan control by “Ambient Temperature
and Discharge Pressure” is a feature that is integral to
the standard software control. If the optional discharge
trans duc er is not installed, the condenser fans will op-
er ate based on outdoor ambient temperature only. See
Table 26.
The condenser fan control by “Discharge Pressure” is
a feature that can be selected if the discharge pres-
sure transducer is installed and fan recycling is not a
con cern. Fan control by discharge pressure will work
ac cord ing to Table 27. The fan control on-pressure and
fan differential off-pressure are pro gram ma ble under
the PROGRAM key.
CONDENSER FAN CONTROL
(YCAL0287 – YCAL0377)
YCAL0287 - YCAL0377 fan control will be by discharge
pressure only. See Tables 29 - 30.
LOW AMBIENT CONDENSER FAN CONTROL
(YCAL0043 – YCAL0253)
(YCAL0287 – YCAL0377 always operate in Low
Am bi ent Mode)
For unit operation below 25°F (-3.9°C) a low ambient
kit is required. The kit consists of a dis charge pres sure
transducer(s) and reversing contactors.
With the low ambient kit installed and the unit pro-
grammed for low ambient operation, the con dens er
fans will op er ate as shown in Table 28 (YCAL0043
– YCAL0253) YCAL0287 – YCAL0377 is shown in
Table 29.
Condenser fan op er a tion in low ambient mode will be
controlled by discharge pressure con trol only.
The fan control on-pressure and the fan dif fer en tial
off-pressure are pro gram ma ble un der the PRO GRAM
key.
A low ambient kit MUST be installed
when “AM BI ENT CONTROL
LOW AM BI ENT” is se lect ed under
the OP TIONS key on YCAL0043
– YCAL0253.
Compressor damage could occur if
programming does not match in stalled
hardware.
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