Carrier 69NT40-541-306 Operation And Service Download

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4–23

T-354

Cd45

Vent Position
Sensor (VPS)

Code Cd45 will display whenever the control detects movement via the sensor
unless alarm 50 is active. The code will display for 30 seconds, then time out
and return to the normal display mode. If the Temperature unit is degrees F, the
VPS units will be CFM and in degrees C the VPS units shall be CMH.

Cd46 Not Used

Cd47

Variable Economy Tem-
perature Setting

The variable temperature "degrees C or degrees F" setting is used with econo-
my mode. Function code is "----" when unit is not configured for economy mode.

Cd48

Dehumidification/
Bulb Mode
Parameter Selection

Code CD48 is used to determine limits (between 60%-95%) for dehumidifica-
tion and/or bulb mode (CNF28) when active.

Cd49

Days Since Last
Successful Pre-trip

Code CD49 will display the number of days since the last successful Auto1, Au-
to2 or Auto3 pre-trip sequence.

Table 4–6 Controller Alarm Indications

CODE

TITLE

DESCRIPTION

AL05

Manual Defrost
Switch Failure

Alarm 05 is triggered if the controller detects continuous Manual Defrost Switch
action for five minutes or more. The alarm will only trigger off when the unit is pow-
er cycled.

AL06

Keypad or
Harness Failure

Alarm 06 is triggered if the controller detects continuous keypad button activity for
five minutes or more. The alarm will only trigger off when the unit is power cycled.

AL07

Fresh Air Vent Open
with Frozen Set Point

Alarm 07 is triggered if the VPS is reading greater than 0 CMH based on the func-

tion code display value and a frozen set point is active.
If AL 50 is active, AL 07 will not be generated.
The alarm will go inactive if the VPS reading transitions to 0 CMH, the set point

transitions to the perishable range, or an AL50 is active.

AL10 CO

Sensor Failure

Alarm 10 is triggered when the CO

sensor voltage is operating outside of the 0.9

v to 4.7 v range, or if the sensor is out of range. This is a display alarm and has
no associated failure action.

AL11

Evaporator Motor
1 IP Trip

Alarm 11 is applicable to units with Single Evaporator Fan Capability (CnF32 set
to 1EFO) only. The alarm is triggered if the evaporator fan motor #1 internal pro-
tector opens. If the alarm is active, probe check is deactivated.

AL12

Evaporator Motor
2 IP Trip

Alarm 12 is applicable to units with Single Evaporator Fan Capability (CnF32 set
to 1EFO) only. The alarm is triggered if the evaporator fan motor #2 internal pro-
tector opens. If the alarm is active, probe check is deactivated.

AL15 Loss of Cool

Alarm 15 is activated when SMV is greater than 15%, unit is in economized or
standard operating modes and Return - Supply Temperature Difference is less
than 0.5C after 4 minutes of compressor run time. The alarm triggers failure ac
tion C (evaporator fan only) or D (all machinery off) if in perishable mode and fail-
ure action D (all machinery off) if a frozen set point has been selected. The alarm
remains active until the unit is power cycled.

AL20

Control Circuit Fuse
Open (24 vac)

Alarm 20 is triggered by control power fuse (F3A, F3B) opening and will cause
the software shutdown of all control units. This alarm will remain active until the
fuse is replaced.

AL21

Micro Circuit Fuse
Open (18 vac)

Alarm 21 is triggered by one of the fuses (F1/F2) being opened on 18 volts AC
power supply to the Controller. The suction modulation valve (SMV) will be
opened and current limiting is halted. Temperature control will be maintained by
cycling the compressor.

Table 4–5 Controller Function Codes (Continued)

CODE

TITLE

DESCRIPTION