21
Alarm 515 for evaporator freeze protection will be initiated
when the sensed water temperature is below the Fluid Freeze
Point + 1°F (0.55°C). Default Fluid Freeze Point = 34°F (1.1°C).
Alarm 531 for low refrigerant temp is activated when the calcu-
lated evaporator suction temperature or measured liquid tem-
perature is less than the Fluid Freeze Point + 1°F (0.55°C). Cool-
er pump will remain on in the case of either alarm.
NOTE: If the chiller is in recycle mode, it will transition to
TRIPOUT, and the CHILLED WATER PUMP will remain on.
The alarm will be clearable when the evaporator saturated refrig-
erant temperature, evaporator refrigerant temperature, leaving
chilled water temperature, and entering chilled water temperature
rise 5°F (2.8°C) above the Fluid Freeze Point.
Condenser Freeze Prevention
This control helps prevent condenser tube freezing by energizing
the condenser pump relay. The PIC6 module controls the pump
and, by starting it, helps to prevent the water in the condenser from
freezing.
When the chiller is off and condenser saturated refrigerant tem-
perature is less than or equal to the condenser freeze point (same
as Brine Freeze Point for 23XRV since unit is not rated for ice du-
ty), the condenser water pump will be energized (Alarm State 511,
Protective Limit - Condenser Freeze). The fault state will clear and
the pump will turn off when the condenser saturated refrigerant
temperature is more than 5°F (2.7°C) above the condenser freeze
point and the entering condenser water temperature is greater than
the condenser freeze point. If the chiller is in recycle shutdown
mode when the condition occurs, the controls will transition to a
non-recycle shutdown.
CONTROL TEST- QUICK TEST
This feature allows the operator to quick-test the controls and re-
lated hardware, including all unit-controlled outputs.
The unit must be off to run the test function. If the unit is on, the
test function cannot be accessed. The test function requires Ser-
vice or Factory access. To access Quick Test the function must
first be activated under the Start / Stop Menu. See Fig. 41.
Upon selection of QuickTest, the Chiller Status and Mode goes
to Service Test; see Fig. 42.
Select QuickTest Menu on the Chiller Start/Stop Screen as a
shortcut to access the Quick Test Menu (an alternate path is
Main MenuQuick). See Fig. 43. All control test parameters
are accessible through the Quick Test Menu. To perform the con-
trol test function, turn appropriable parameter On or set to de-
sired value and then verify output. See Fig. 44.
Unless otherwise noted, all protective limits remain active during
the controls test.
Fig. 41 — Quick Test
Fig. 42 — Quick Test — Service Test
Fig. 43 — Quick Test Menu
Fig. 44 — Quick Test A
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