York MILLENNIUM YCAL0043SC, Руководство пользователя, Страница: 61 / 133

YORK INTERNATIONAL
61
FORM 150.62-NM2
S Y S 1 S P = 7 2 . 1 P S I G
D P = 2 2 7 . 0 P S I G
These displays show suction and discharge pressures
for systems 1 & 2. The discharge pressure transducer
is optional on all models
If the optional discharge transducer is not installed, the
discharge pressure would display 0 PSIG (0 BARG).
Some models come factory wired with a low pressure
switch in place of the suction transducer. In this case,
the suction pressure would only be displayed as the
maximum suction pressure reading of >200 PSIG (13.79
BARG) when closed, or < 0 PSIG (0 BARG) when open.
The minimum limits for the display are:
Suction Pressure: 0 PSIG (0 BARG)
Discharge Pressure: 0 PSIG (0 BARG)
The maximum limits for the display are:
Suction Pressure: 200 PSIG (13.79 BARG)
Discharge Pressure: 400 PSIG (27.58 BARG)
The above two messages will appear sequentially for
each system. The first display shows accumulated run-
ning hours of each compressor for the specific system.
The second message shows the number of starts for
each compressor on each system.
This display of the load and unload timers indicate the
time in seconds until the unit can load or unload. Whether
the systems loads or unloads is determined by how far
the actual liquid temperature is from setpoint. A detailed
description of unit loading and unloading is covered un-
der the topic of Capacity Control.
The display of COOLING DEMAND indicates the cur-
rent “step” in the capacity control scheme. The number
of available steps are determined by how many com-
pressors are in the unit. In the above display, the “2”
does not mean that two compressor are running but only
indicates that the capacity control scheme is on step 2
of 8. Capacity Control is covered in more detail in this
publication which provides specific information on com-
pressor staging.
This display indicates the current LEAD system. In this
example system 2 is the LEAD system, making system
1 the LAG compressor. The LEAD system can be manu-
ally selected or automatic. Refer to the programming
under the “Options” key.
A unit utilizing hot gas bypass should be
programmed for MANUAL with system
1 as the lead system. Failure to do so
will prevent hot gas operation if system
2 switches to the lead system when pro-
grammed for AUTOMATIC LEAD/LAG.
S Y S 2 S P = 7 3 . 6 P S I G
D P = 2 1 9 . 8 P S I G
S Y S X H O U R S 1 = X X X X X
2 = X X X X X, 3 = X X X X X
C O O L I N G D E M A N D
2 O F 8 S T E P S
L E A D S Y S T E M I S
S Y S T E M N U M B E R 2
L O A D T I M E R = 5 8 S E C
U N L O A D T I M E R = 0 S E C
S Y S X S T A R T S 1 = X X X X X
2 = X X X X X, 3 = X X X X X
2