MP-3000a Controller
65
Changing the Setpoint
NOTE: Humidity control, humidity setpoint and
economy mode can also be set from the Setpoint
menu. See “Setpoint Menu” under Menu
Operating Instructions in this chapter.
To change the controller setpoint, turn the unit
On/Off switch ON. With the standard LCD
message display showing on the controller (i.e.
setpoint temperature):
1. Press the SETPOINT key. The SETPOINT
menu appears with the cursor in the “TEMP
SETP” line.
2. Press the F4 key. An Enter Arrow appears in
the menu line and the current setpoint
disappears.
3. Enter (type) the new setpoint in the LCD
display using the general purpose keypad. To
enter a minus setpoint, press the EXIT (+/-)
key first. The cursor moves to the right of the
screen as each key entry is acknowledged and
displayed.
NOTE: Always check that the setpoint
entered in the LCD display is correct before
proceeding.
4. Press and hold the F4 key until the cursor
stops flashing. The new setpoint is recorded in
the controller and appears in the LCD display.
NOTE: If the setpoint is not entered within
30 seconds, the controller will default
(return) to the previous setpoint. If this
occurs, repeat steps 1 through 4.
Initiating a Manual Defrost
With the unit On/Off switch ON:
1. Press the DEFROST key.
•
If the unit operating conditions allow a manual
defrost (e.g. evaporator coil temperature is
less than 18 C [56 F]), the unit enters defrost
as the Defrost and Heat LEDs turn ON. LCD
message display shows “DEFROST
ACTIVATED”.
•
If unit operating conditions do NOT allow
defrost, the LCD message display shows
“DEFROST NOT ACTIVATED”.
2. The defrost cycle automatically terminates.
NOTE: If frost or ice can not be removed from
the evaporator coil by an automatic defrost cycle,
a “timed” defrost of the evaporator coil can be
performed:
• Activate HEAT ON in the Manual Function
Test sub-menu.
• Then press “5” key six times. Heaters will be
activated for 70 minutes. Unit then returns to
normal operation.
Displaying Alternate
Controlling (Supply or Return)
Air Sensor Temperature
The controller can show either the supply or
return air temperature in the LED Display. With
the unit On/Off switch ON and the controller
showing the standard LED Display:
1. Check the indicator LEDs to determine which
sensor temperature (supply air or return air)
currently appears in the right display. This is
the controlling sensor.
2. To view the alternate (supply or return) air
temperature, press and hold the SUP/RET key.
The controller will show the alternate sensor
temperature as long as the SUP/RET key is
depressed.
3. The display then returns to the controlling
sensor temperature when the SUP/RET key is
released.
Summary of Contents for CRR-40 119
Page 4: ......
Page 16: ...Safety Precautions 16...
Page 18: ...Service Guide 18...
Page 20: ...Model Features 20...
Page 32: ...Specifications 32...
Page 120: ...MP 3000a Controller 120...
Page 160: ...Wiring and Schematic Diagrams Index 160...
Page 161: ...161 MPC2000 Wiring Schematic...
Page 162: ...162 MPC2000 High Voltage Wiring Diagram...
Page 163: ...163 MPC2000 Low Voltage Wiring Diagram...
Page 164: ...164 MPC2000 WCC Wiring Schematic...