McQuay AGZ 035A, Installation, Operation And Maintenance Manual

Page: 49 / 96

IOMM AGZ-3 AGZ 035A through 065A 49
Adjustable Points
The following McQuay Global Scroll Chiller points are adjustable by the Zone Terminal.
Table 16, Adjustable Points
TEMPLATE VALUES
NAME FACTORY SETPOINT RANGE
OA/AI3 HiLim SP 80°F 0 to 100°F
OA/AI3 Reset SP -40°F -100 to 100°F
LvgWtr Rband SP 0°F 0 to 15°F
Unoccpd Lvg SP 70°F 40 to 90°F
OA Lockout SP -10°F -20 to 65°F
Lvg Low Lim SP 20°F 20 to 40°F
SoftSta Capcty 50% 0 to 100%
SoftStart Time 2 min 0 to 20 minutes
Zone Terminal Glossary
Lvg Water Temp - Shows the temperature of the water leaving the evaporator.
Evap Pres #1 - Shows the evaporator pressure for refrigerant circuit #1.
Evap Pres #2 - Shows the evaporator pressure for refrigerant circuit #2.
OA/AI3 Input - Reset input signal (Outdoor Air Temp. is standard), non-adjustable
OA/AI3 HiLimSP - Used in algorithm for Outside Air Reset. Adjusts Outdoor Air High Limit
(OAHL)(default is 80°F).
OA/AI3 Reset SP - Used in algorithm for Outside Air Reset. Adjusts Outdoor Air Reset Band
(OARB)(default is -40°F; therefore outdoor air reset is 40-80°F).
Lvg Water SP - Shows the dial adjustment setpoint. Non-adjustable from ZT.
LvgWtr Rbnd SP - Can be adjusted through the ZT, 0° - 15°F (default is 0°F). Used in algorithm for
Outside Air Reset. (For an example of 10°F reset; 45°F Leaving Water Setpoint reset up to
55°F).
Contrl Band SP - Indicates what the Control Band Knob is set at. Non-adjustable from ZT.
Actual Lvg SP - Shows the actual setpoint, including any reset that is occurring.
Unoccpd Lvg SP - Adjustable from 40°F - 90°F (default is 70°F). The setpoint is activated by a
timeclock in unoccupied mode.
OA Lockout SP - Adjustable from -20°F to 65°F (default is -10°F). Shuts the unit off when the
Outside Air reaches the setpoint. (Differential = 5°F).
% Unit Load - Indicates the % of the unit load.
Lvg Low Lim SP - Adjustable from 20°F - 40°F (default is 20°F). This control that will shut the
chiller off based on the leaving water temperature going below this setpoint. NOTE: This can be
replaced with
Low Pres Freezstat SP on some units.
SoftSta Capcty - Adjusts the ramping of steps from 0% - 100% (default is 50%).
SoftStart Time - Adjustable ramping time from 0 - 20 minutes (default is 2 minutes).
Cir #1 Starts - Counts the number of starts for circuit #1.
Cir #2 Starts - Counts the number of starts for circuit #2. Note: If power is lost to the controller, this
data is lost and will start counting over. When power is applied and kept on, the controller will
allow 10 starts for circuit #1 as the lead circuit, then will switch to circuit #2 for the next 10
starts, etc (Automatic Lead/Lag).
Occupied - |= On, 0 = Off
Flow Failure - |= Alarm, 0 = Normal