Unit Warning
The low battery message is not a unit safety and will not
be logged to the history buffer. It is a unit warning and
will not auto-restart. Operator intervention is required to
allow a re-start of the chiller.
T h e l o w b a t t e r y w a r n i n g w i l l o n l y o c c u r a t
microprocessor power-up, when the RTC battery is
checked. If a low battery is found, all programmed
setpoints, program values, options, time, schedule, and
history buffers will be lost. These values will all be reset
to their default values which may not be the desired
operating values.
Once a faulty battery is detected, the unit will be
prevented from running until the 'PROGRAM' key is
pressed. Once 'PROGRAM' is pressed the anti-recycle
timers will be set to allow the operator time to check
setpoints, program values, and options.
If a low battery is detected, it should be
r e p l a c e d a s s o o n a s p o s s i b l e . T h e
programmed values will all be lost and the unit
will be prevented from running on the next
power interruption. The RTC/battery is
located at U5 on the IPU II board.
5
Display/Print Keys
The Display/Print keys allow the user to retrieve system
and unit information that is useful for monitoring chiller
o p e r a t i o n ,
d i a g n o s i n g
p o t e n t i a l
p r o b l e m s ,
troubleshooting, and commissioning the chiller.
System and unit information, unit options, setpoints, and
scheduling can also be printed out with the use of an
optional printer. Both real-time and history information
are available.
5.1
OPER DATA Key
The 'OPER DATA' key gives access to unit and system
operating parameters. When the 'OPER DATA' key is
pressed, system parameters will be displayed and
remain on the display until another key is pressed. After
pressing the 'OPER DATA' key, the operating data
messages can be scrolled through by using the 'UP
ARROW' and 'DOWN ARROW' keys.
The following operating data messages will be
displayed in the order shown:
This display shows chilled leaving liquid temperature.
The minimum display limit is -19.0°C and the maximum
display limit is 60.1°C.
This display shows the ambient air temperature. YLAA
and YLAE units only.
The minimum display limit is -17.4°C and the maximum
display limit is 55.2°C.
On YCWL/YCRL units the display will read < -17.4C
1
-
19
Form 201.26.OI1(11/09)
!
!
L O W
B A T T E R Y
!
!
C H E C K
P R O G /
S E T P /
O P T N
L C H L T
=
6 .
2 ° C
A M B I E N T
A I R
T E M P
< - 1 7 . 4 ° C
