Sequence Of Operation; Electro-Mechanical Controls; Microprocessor Controls; Operation - Carrier AirStream 42WKN08-36 Installation, Operation And Maintenance Manual

Sequence of Operation

ELECTRO-MECHANICAL CONTROLS

A 24-v signal from the thermostat to terminal G supplies power
to the blower motor(s), condensate pump, and vane motor (if
equipped). A toggle switch on the control box can be used to
switch the oscillating vanes on or off. The condensate pump will
run continuously, as long as the blower is energized. A call for
heating, at terminal W, or cooling, at terminal Y, will energize
the water valve actuator and allow water to flow through the cas-
sette coil. When the call for heating or cooling is satisfied, the
valve will close.
If the temperature drops below the set point of the coil freezestat,
the water valve with automatically open to circulate water
through the coil.
If the condensate float switch detects a high level of water in the
condensate tray, the switch will open, activate the condensate
pump and disable the heating/cooling signal until the water level
drops down to normal.

MICROPROCESSOR CONTROLS

The microprocessor monitors indoor coil temperature and re-
turn-air temperature. The receiver contains a self-diagnostic
feature. When a low indoor coil temperature is detected, the
cooling action is stopped. If a sensor fails, then an alarm is
displayed on the fascia mounted receiver.

OPERATION

When using the IR transmitter (see Fig. 35), always point the
transmitter head directly at the receiver. At the time of trans-
mission, the transmit indicator symbol will display and an au-
dible alarm will be heard if the signal has been received.
When the batteries are first installed, the transmitter or op-
tional pendant default set point will be 64°F, low fan speed
will be selected, and the system will be set to cool only mode.
When a parameter is changed in the Remote Control, it must
be sent to the thermostat by pressing ON/SEND.
Refer to Fig. 35 for button locations.

On/Off

Press the ON/SEND button to activate the air conditioner /
fan coil unit and/or update information.

Fan Speeds

Press the FAN button to switch between fan speeds:
• High Speed
• Medium Speed
• Low Speed
• Auto Speed
Press the ON/SEND button to send information to thermostat.

Modes

Press the MODE button to switch between unit modes:
• Cool
• Heat
• Auto change-over
• Fan only
Press the ON/SEND button to send information to thermostat.

Temperature Setpoint

Adjust the desired temperature using the (+) or (–) buttons.
Press the ON/SEND button to send information to thermostat.

Clock

1. Press the SELECT button. CLOCK SET will flash.
2. Press the (+) or (–) buttons. The hours will flash.
3. Adjust the hours using the (+) or (–) buttons.
4. Press the SELECT again. Minutes will flash.
5. Adjust the minutes using the (+) or (–) buttons.
6. Press the SELECT again to return to normal display
mode.
7. Press the ON/SEND button to send information to the
thermostat.

Timer

IMPORTANT: While setting the timer, if no button is
pressed for 10 seconds, the display will return to normal
display mode.
Start Time
1. Press the SELECT button twice. PROGRAM and
START (flashing) will appear on display.
2. Press the SELECT button. The hours will flash.
3. Adjust the hours using the (+) or (–) buttons.
4. Press the SELECT button. The minutes will flash.
5. Adjust the minutes using the (+) or (–) buttons.
Stop Time
1. Press the SELECT button. PROGRAM & STOP (flash-
ing) will appear on display.
2. Press the SELECT button. The hours will flash.
3. Adjust the hours using the (+) or (–) buttons.
4. Press the SELECT button. The minutes will flash.
5. Adjust the minutes using the (+) or (–) buttons.
6. Press the SELECT button. The TIMER will blink.
7. Select TIMER ON (black timer icon) or OFF (white
timer icon) using the (+) or (–) buttons.
8. Press the ON/SEND button to send the information to the
thermostat.
NOTE: When the Timer is active, and there is power failure to
the thermostat, the display will show "ON" flashing.

Battery Replacement

When the batteries are low, the remote control display will
dim. If the batteries are not replaced, the display will turn off
completely.
1. Pull the battery cover down to reveal the batteries.
2. Remove the old batteries.
3. Wait for 10 minutes before installing the new batteries.
4. Install 2 new AAA batteries. Pay attention to the polarity.
5. Replace the battery cover.
IMPORTANT: The remote control will not operate un-
less at least 10 minutes pass between removing the old
batteries and installing the new ones.
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