Product manual
IOMM ACR/AGR-1 77
Menu #6: Circuit 62 PressuresThe circuit #2 evaporator and condenser refrigerant pressure
readings are displayed under this menu. The calculated minimum and maximum condenser pressure
values are also shown.
Menu #7: Circuit #l TemperaturesThe circuit #I refrigerant temperatures are calculated from their
corresponding pressure sensors and displayed here. If the optional Sensors are not present, the line
item will flash “Open”.
Menu #8: Circuit #2 TemperaturesThe circuit #2 refrigerant temperatures are calculated from their
corresponding pressure sensors and displayed here. If the optional sensors are not present, the line
item will flash “Open”,
Menu#9: Chiller AmpsDisplays the present amp draw of the chiller expressed as a percentage of the
unit rated load amps under full load conditions (optional feature).
Menu #10: Compressor Run HoursThe total run hours for each compressor is available under this
menu.
Menu #11: Compressor StartsThe total number of starts for each compressor is available under this
menu.
Menu#12: Air TemperatureDisplays the current outdoor air temperature if the optional OAT sensor
is installed on the air cooled chiller and “Lcl” is selected from Menu 23. Also displayed here is the air
temperature received from a network if the “Rmt” OAT select option from Menu 23 is selected.
Control Menus
Menus 13 through 23 are the set point menus. All adjustable control parameters and set points, time
schedules, control options, and alarm thresholds are accessed through these menus.
CAUTION
Any changes to these parameters must be determined and implemented by qualified
personnel with a thorough understanding of how these parameters affect the
operation of the unit. Negligent or improper adjustment of these controls may result
in damage to the unit or personal injury.
Menu #13: Control ModeOne of several automatic and manual operating modes may be selected
from within this menu. Typically, the selected control mode will be Automatic which will allow the
MicroTech controller to handle all compressor and condenser fan staging. Refrigerant circuit #2 may
be locked off while still allowing circuit #1 to stage automatically by selecting AutoCir#1 -Off#2 as the
operating mode. OffCirc#1 -Auto#2 allows the normal staging of refrigerant circuit #2 but circuit #1 is
locked off. Select Manual Staging if manual control is desired. In this operating mode, the MicroTech
controls the condenser fans but the number of stages is determined manually via the keypad. If
manual staging is selected, the second item under this menu indicates the number of active cooling
stages. Use the INCR or DECR keys to increase or decrease the number of active stages.
Menu#14: Leaving Water Set PointsThe leaving wafer set points, control band, maximum pull down
rate and water reset options are adjusted from this menu. The first menu item is The Active Set Point
("Active Spt"). The current control temperature is displayed here. The Leaving Chilled Water Set Point
("Lvg Evap") appear towards the top of this menu. These are the set points that will be maintained for
chillers if no reset options are in effect. The Active Control Set Point ("Active Spt") will display the
calculated chilled or heated water temperature to be maintained when one of the reset options is
enabled.