Carrier 48TC series, Service And Maintenance Instructions, Page: 63 / 112

63
LEGEND
* Table 26 illustrates the complete hierarchy. Your menu parameters
may be different depending on your configuration. For example, if
you do not have a DCV (CO
2
) sensor, then none of the DCV param -
eters appear.
† When values are displayed, pressing and holding the or button
causes the display to automatically increment.
** — = Not Applicable.
†† ERV Operation: When in cooling mode AND the conditions are NOT
OK for economizing - the ERV terminal will be energized. In the Heat -
ing mode, the ERV terminal will be energized when the OA is below
the ERV OAT set point in the set point menu.
*** After 10 minutes without a command or mode change, the controller
will change to normal operation.
NOTES:
1. STATUS —> OCCUPIED — The factory-standard Occupancy sig -
nal originates with a thermostat or other controller call for indoor
fan operation at CTB terminal G. This signal passes through the
Central Terminal Board’s OCCUPANCY jumper to the ECONO
connector and to the W7220’s OCC input terminal. An external
timeclock or relay is required to implement an Occupancy schedule
on the economizer damper position.
2. STATUS —> MA TEMP, SETPOINTS —> MAT SET — The W7220
menu parameters and labels include designations MA, MAT and
Mixed Air for the economizer cooling control sensor. On these roof-
top units, the economizer control sensor is located downstream of
the evaporator/indoor coil in the supply fan section where this sen-
sor is designated as Supply Air Temperature (SAT) sensor.
3. SETPOINTS —> DRYBLB SET — This point is not displayed if a
Return Air (differential) temperature sensor or an Outdoor Air
enthalpy sensor is connected.
4. SYSTEM SETUP parameters must be configured as noted for 2-
Speed unit operation:
EQUIPMENT = CONV
AUX2 I = W
FAN SPEED = 2SPEED
For damper minimum position settings and checkout menu read -
ings, see Table 27. For dry bulb operation with a 1-speed fan, with
or without DCV, see Tables 28 and 29. For enthalpy operation
with a 1-speed fan, with or without DCV, see Tables 30 and 31.
For dry bulb operation with a 2-speed indoor fan, with or without
DCV, see Tables 32 and 33. For enthalpy operation with a 2-speed
indoor fan, with or without DCV, see Tables 34 and 35.
ALARMS
(cont)
RA SYLK T ERR — — RETURN AIR S-BUS SENSOR ERROR
Return air enthalpy sensor has failed or become disconnected -
check wiring, then replace sensor if the alarm continues.
RA SYLK H ERR — —
DA SYLK T ERR — —
DISCHARGE AIR S-BUS SENSOR ERROR
Discharge air sensor has failed or become disconnected - check
wiring, then replace sensor if the alarm continues.
OA SENS T ERR — —
OUTSIDE AIR TEMPERATURE SENSOR ERROR
Outdoor air temperature sensor has failed or become
disconnected - check wiring, then replace if the alarm continues.
ACT ERROR — —
ACTUATOR ERROR
Actuator has failed or become disconnected - check for stall,
over voltage, under voltage and actuator count. Replace actuator
if damper is movable and supply voltage is between 21.6 V and
26.4 V. Check actuator count on STATUS menu.
FREEZE ALARM — —
Check if outdoor temperature is below the LOW Temp Lockout on
set point menu. Check if Mixed air temperature on STATUS
menu is below the Lo Set point on Advanced menu. When
conditions are back in normal range, the alarm will go away.
SHUTDOWN ACTIVE — —
AUX2 IN is programmed for SHUTDOWN and 24 V has been
applied to AUX2 IN terminal.
DMP CAL RUNNING — —
DAMPER CALIBRATION ROUTINE RUNNING
If DCV Auto enable has been programmed, this alarm will display
when the W7220 is completing a calibration on the dampers.
Wait until the calibration is completed and the alarm will go away.
Must have OA, MA and RA sensors for DCV calibration; set up is
in the Advanced setup menu.
DA SENS ALM — —
DISCHARGE AIR TEMPERATURE SENSOR ALARM
Discharge air temperature is out of the range set in the
ADVANCED SETUP Menu. Check the temperature of the
discharge air.
SYS ALARM — —
When AUX1-O is set to SYS and there is any alarm (e.g., failed
sensors, etc.), the AUX1-O terminal has 24 vac out.
ACT UNDER V — —
ACTUATOR VOLTAGE LOW
Voltage received by actuator is above expected range.
ACT OVER V — —
ACTUATOR VOLTAGE HIGH
Voltage received by actuator is below expected range.
ACT STALLED — —
ACTUATOR STALLED
Actuator stopped before achieving commanded position.
Table 26 — W7220 Menu Structure* (cont)
MENU PARAMETER
PARAMETER
DEFAULT
VALUE
PARAMETER
RANGE AND
INCREMENT
†
EXPANDED PARAMETER NAME
Notes
CLO —
Compressor Lockout
ERV — Energy Recovery Ventilator
LCD —
Liquid Crystal Display
MA — Mixed Air
MAT —
Mixed Air Temperature
— — Not Applicable
OA —
Outdoor Air
OAT — Outdoor Air Temperature
OCC —
Occupied
RA — Return Air
RAT —
Return Air Temperature
RTU — Rooftop Unit
SYS —
System