24
Cooling Mode
General Cooling Control
Depending on the control type, the Occupied Cooling Mode allows the cooling to operate
as needed and is activated whenever the room or outside air temperature is 2° above the
cooling setpoint. During the Unoccupied Cooling Mode, the cooling is activated
whenever the room or outside air temperature is at the cooling setpoint and is deactivated
2°F below the cooling setpoint. In the Cooling Mode the cooling output will cycle to
maintain a constant room temperature. The cooling outputs are protected by an anti-cycle
timer which has a 3 minute off / 3 minute on delay. Additionally, the fan is required to be
running before any cooling outputs are enabled.
To change the desired cooling temperature of an MDT or MRT control system, rotate the
temperature setpoint knob on the
remote control panel
clockwise to the desired
temperature. The allowable temperature range is 55°F - 90°F. The cooling will be
disabled when the temperature drops to the Cooling Setpoint.
To change the desired cooling room temperature of an MRT-Expert control system, scroll
through the SETPOINTS menu tree using the
BACview
, locate the Occupied Cooling
Setpoint, and enter a new temperature. The allowable temperature range is 40°F - 130°F.
Additionally, on all controls systems except the MDT and MDT-EXPERT the control
system cycles the cooling output to maintain the supply air temperature within a defined
operating window. This window defines the maximum and minimum discharge
temperatures.
To change the desired minimum supply or discharge air temperature scroll through the
SETPOINTS menu tree, locate the CLG MIN DA Setpoint, and enter a new temperature.
This temperature must not be greater than the CLG MAX DA Setpoint. The allowable
temperature range is 40°F - 130°F. This sets the lowest discharge air temperature that will
leave the unit.
To change the desired maximum supply or discharge air temperature scroll through the
SETPOINTS menu tree, locate the CLG MAX DA Setpoint, and enter a new
temperature. This temperature must not be less than the CLG MIN DA Setpoint. The
allowable temperature range is 40°F - 130°F. This sets the highest discharge air
temperature that will leave the unit.
If the maximum and minimum discharge temperature setpoints are set too closely
together, the condenser may cycle excessively.
Energy Savings Mode 4
Energy Savings Mode 4 will automatically disable the cooling if the outside air
temperature is below the Cooling Economizer setpoint. This function is similar to an inlet
duct thermostat. The cooling will cycle back on if the outside air temperature rises 3°F
above the Cooling Economizer setpoint.
To change the desired cooling economizer temperature scroll through the SETPOINTS
menu tree, locate the COOLING ECONOMIZER Setpoint, and enter a new temperature.
The default for this setpoint is 55°F. The allowable temperature range is 40°F - 130°F.
