York YCAS0295EB, Installation Operation & Maintenance

Page: 139 / 194

139 YORK INTERNATIONAL
FORM 201.19-NM7 (804)
3.3 SYSTEM # DATA KEYS
Pressing one of the System # Data keys a number
of times scrolls through displays of differential oil
pres sure (OIL), suction pressure (SP) and discharge
pres sure (DP), oil temperature, suction temperature
(ST), dis charge temperature (DT), saturated suction
tem per a ture, suction superheat, saturated discharge
tem per a ture, discharge superheat and compressor slide
valve position.
Examples of these displays are shown where # is the
appropriate system number:
The Evaporator Inlet Temp. display
will only appear if the chiller is selected
for R407C.
Temperatures and pressures are either mea sured di rect ly
by transducers and tem per a ture sensors, or com put ed
from these mea sure ments as follows:
Saturated discharge and suction temperatures are
com put ed by converting measured pressure to tem-
perature.
Slide Valve Position is computed based on the number
of loading steps that the micro has sent to the slide
valve solenoid in the form of a voltage signal. To the
mi cro pro ces sor, STEP 0 = fully unloaded and STEP 75
= fully loaded.
A M B I E N T A I R T E M P
= 7 1 . 9 ° F
S # S A T D S C H = 1 3 0 . 0 ° F
D S C H S H E A T = 5 4 . 3 ° F
S Y S # S V S T E P = 3 7
S Y S # C O O L E R I N L E T
R E F R I G T E M P = 2 8 . 2 ° F
S Y S # O I L = 1 7 6 P S I G
S P = 6 4 D P = 1 9 5 P S I G
S Y S # O I L = 1 5 7 . 4 ° F
S T = 3 1 . 0 D T = 1 2 3 . 2 ° F
S # S A T S U C T = 3 2 . 9 ° F
S U C T S H E A T = 1 5 . 0 ° F
Slide valve position is AP PROX I MATE
and should be used for ref er ence only.
Under actual conditions the com-
pres sor may be ful ly load ed be tween
step 60 - 75 and fully un load ed be tween
step 0 - 35.
Superheats are the difference between the respective
sat u rat ed temperature (converted from pres sure) and the
ac tu al. Display Lim its for the Sys tem Pressures and
Tem per a tures displays are as follows:
Minimum and maximum values may
change as software (EPROM) re vi -
sions are made.
*
Below 9.0°F (13°C), the Suction
Temp. display will disappear. This will
in turn cause the Su per heat display to
dis ap pear.
3.4 AMBIENT TEMP KEY
When the Ambient Temperature key is pressed, am bi ent
air temperature, as mea sured sur round ing the chill er, is
displayed.
Display Limits: Minimum - 4.6°F (-20.3°C)
Maximum 137.9°F (58.8°C)
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MIN. LIMIT MAX. LIMIT
Oil Pressure 208 PSID (14 Bar) 0 PSID (0 Bar)
Suction Pressure 0 PSIG (0 Bar) 199 PSIG (14 Bar)
Discharge Pressure 0 PSIG (0 Bar) 399 PSIG (28 Bar)
Suction Temp. 9.0 °F (-13°C) 84.2 °F (29°C)
Discharge Temp. 40.3 °F (5°C) 302.6 °F (150°C)
Oil Temp. 40.3 °F (5°C) 240.0 °F (116°C)
Sat. Discharge Temp. -41.0 °F (-41°C) 140.5 °F (60°C)
Sat. Suction Temp. -41.0 °F (-41°C) 101.3 °F (39°C)
Slide Valve Position 0% (0%) 100% (100%)
Suction Superheat -81.5 °F (-63.1°C) 60.9 °F (16°C)
Discharge Superheat 22.5 °F (-5.3°C) 216.0 °F (102.2°C)
*
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