-KCOL
(YLAE and YCWL/YCRL Units only))
Each compressor contactor is fitted with a thermal
overload to provide single phase and overload
protection to EN60947-4-1 tripping category class 10 A.
The overload requires resetting after a trip.
-FHP
On YLAA models the mechanical HP switch opens at
38.7 barg.
On YLAE models the first mechanical (manual reset) HP
switch opens at 38.7 barg. On models 0255SE / 0265HE
and above a second mechanical HP switch is fitted, this
opens at 40.3 barg.
On YCWL/YCRL models the first mechanical (manual
reset) HP switch opens at 34.7 barg. The second
mechanical HP switch opens at 36.3 barg.
The 'SYS MP/HPCO INHIBIT' message indicates that if
the shutdown was due to a motor protector, that when
the motor protector resets the system will restart
automatically. If the shut down was due to the
mechanical high pressure cut-out, then the cut-out must
be reset before the system can restart.
The 'SYS MP/HPCO FAULT' message indicates that
the system has locked out and requires a electrical
reset, in the case of a mechanical high pressure cut-out,
a device reset.
Unit Safeties
Unit safeties are faults that cause all running
compressors to be shut down.
The low leaving chilled liquid temperature cut-out
protects the chiller form an evaporator freeze-up should
the chilled liquid temperature drop below the freeze
point. This situation could occur under low flow
conditions or if the microprocessor setpoint values are
improperly programmed. Anytime the leaving chilled
liquid temperature (water or glycol) drops below the
cut-out point, the chiller will shutdown. Restart can occur
when chilled liquid temperature rises 1.2°C above the
cut-out.
The under voltage safety assures that the system is not
operated at voltages where malfunction of the
microprocessor could result in system damage. When
the 115 Vac to the microprocessor drops below the limit,
a unit fault is initiated to safely shut down the unit.
Restart is allowed when the 115 Vac is within limits and
the anti-recycle timers have finished counting down,
u n l e s s M A N U A L P O W E R F A I L R E S T A R T i s
programmed under the OPTION key. In this case the
unit switch must be set to OFF then back to ON to reset
this trip.
YLAA and YLAE Units with Optional Hydro Kit
On units with one pump:
This indicates the manual
motor starter protecting the pump from short circuit or
overload conditions has tripped or been set to OFF.
Setting the device to on will reset the trip.
On units with two pumps, duty and standby
: This
indicates that both the manual motor starters protecting
the pumps from short circuit or overload conditions have
tripped or both have been set to OFF. Setting at least
one of the devices to on will reset the trip.
On units with one pump:
After the 30 second stop to
start timer has timed out, the pump is started if there is a
'Leaving Liquid Temperature Cutout', or any of the
compressors are running, or with the daily schedule not
calling for a shutdown with the unit switch on and the
remote stop/start input closed (terminals 13 & 14 on
-ARB circuit board). If the flow switch does not close
within 10 seconds the unit locks out on UNIT FAULT:
PUMP FAIL MAKE FLOW and the pump is stopped.
Setting the unit switch to OFF then back to ON will reset
the trip.
On units with two pumps, duty and standby:
After
the 30 second stop to start timer has timed out the pump
is started if there is a 'Leaving Liquid Temperature
Cutout', or any of the compressors are running, or with
the daily schedule not calling for a shutdown with the
unit switch on and the remote stop/start input closed
(terminals 13 & 14 on -ARB circuit board). If the flow
switch does not close within 10 seconds the running
pump is stopped and the standby pump is started. If in a
further 10 seconds the flow switch does not close the
unit locks out on UNIT FAULT: PUMP FAIL MAKE
FLOW and the running pump is stopped. Setting the unit
switch to OFF then back to ON will reset the trip. In
attempting to clear this fault check that one of the
manual motor starters protecting the pumps has not
tripped.
1
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18
Form 201.26.OI1(11/09)
U N I
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F A U L T :
L O W
L I
Q U I
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T E M P
U N I
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F A U L T :
1 1 5 V A C
U N D E R
V O L T A G E
U N I T
F A U L T :
P U M P
T R I P
U N I T
F A U L T :
P U M P
F A I L
M A K E
F L O W
