Carrier 33CS Installation, Service, And Troubleshooting Instructions Download

Page: 27 / 32

CONFIGURATION TO ACTIVATE ALARM — To activate
a space temperature alarm, configure the Comfort Trend
Demand set point to any value except 0. Configure the Com-
fort Trend Time Limit set point.
CONFIGURATION TO NORMALIZEALARM — The
space temperature alarm will automatically clear when the sys-
tem can properly condition the space. To remove any alarms,
follow the procedure to clear the alarm from the thermostat and
network using manual reset.
CONFIGURATION EXAMPLE

Occupied Space Cooling Set Point:

72 F

Occupied Space Heating Set Point:

68 F

Comfort Trend Demand:

4.5 F

Comfort Trend Time Limit:

7 minutes

The system is operating normally without alarm during the

cooling mode. The trend of the space temperature indicates that
the system is unable to keep the space within set points, and
space temperature rises to 76.5 degrees F. The trend of the
space temperature is not improving, and temperature condi-
tions are getting worse for at least seven minutes. At that time,
a space temperature (Comfort Trend) alarm (SE01) is initiated.
The alarm will automatically clear when the system can prop-
erly maintain space temperature conditions within the space.

The alarm is removed using the manual reset. The system

will not return to normal without being reset.
CLEARING THE ALARM FROM THE THERMOSTAT —
Space temperature alarms can be cleared or ‘‘erased’’ from the
system in 3 ways:
• Cycle power to the thermostat OFF, then ON.
• Reset the Unit Thermostat. Initiate a reset by switching the

Unit Reset option to the ON configuration (category 7,
option 11).

• Switch the configuration value for Comfort Trend Demand

or the Comfort Trend Time Limit to zero, then back to an
acceptable range (category 7, options 4 or 5).

Discharge-Air Temperature Alarm (Heat/Cool
Mode Error) —

See Table 7 for Discharge-Air Tempera-

ture alarm specifications.

Table 7 — Discharge Air Temperature Alarm

OPERATION
Heating Mode — Alarm is issued when unit discharge temper-
ature is not above the heating mode error set point.
Cooling Mode — Alarm is issued when unit discharge tem-
perature is not below the cooling mode error set point.
CONFIGURATION TO ACTIVATE ALARM — To activate
alarm, configure error set points for Heat/Cool mode (0 to
140 F). An automatic 10-minute warm-up/cool-down period is
initiated before any temperature checking begins.

CONFIGURATION TO NORMALIZE ALARM — When
unit discharge temperature rises above the heat mode error set
point, the heat mode alarm is normalized. When unit discharge
temperature drops below the cool mode error set point, the
cool mode alarm is normalized.

For example, the Heating/Cooling Mode Error set points are

90 and 55 F. During a heat mode, after 10-minute heating peri-
od, if discharge temperature does not increase above 90 F, a
heat mode error is generated. After discharge temperature in-
creases to above 90 F, the alarm is normalized.

During cooling mode, after a 10-minute cooling period, if

discharge temperature does not drop to below 55 F, a cool
mode error is generated. After the discharge temperature de-
creases to below 55 F, the alarm is normalized.
CLEARING THE ALARM FROM THE THERMOSTAT —
Heat/Cool Mode Alarms are cleared or ‘‘erased’’ from the sys-
tem in 2 ways:
• Cycle power to the thermostat OFF, then ON.
• Reset the unit thermostat. Initiate a reset by switching the

Unit Reset to the ON configuration (category 7, option 11).

Fan Status Alarm —

Refer to Table 8 for Fan Status

Alarm specifications.

Table 8 — Fan Status Alarm

OPERATION
The detecting or verifying fan is running. The fan relay is on
or Heat 1 relay is on.

When the TEMP system thermostat indicates commanded

state of FAN (relay) is on, but flow switch indicates no airflow
after 30-second time delay (sensor contacts still open), an
alarm condition is initiated (heat or cool or ventilation mode).

When the TEMP system thermostat indicates commanded

state of HEAT 1 (relay) is on, but flow switch indicates no air-
flow after 120-second delay time (sensor contacts still open),
an alarm condition is initiated. This delay time allows for units
having internal control of heat, versus thermostat control of
heat.

When an alarm condition is initiated:

• system mode (either heat or cool) is dropped
• alarm SE06, Cannot Detect Fan ON, is issued
• A manual reset is required to reset the alarm
Detecting or Verifying Fan is OFF. Fan Relay is OFF and
Heat 1 Relay OFF — When the TEMP system thermostat in-
dicates commanded state of FAN (relay) is OFF, but flow
switch indicates that airflow still exists after 240-second delay
time from fan off command (sensor contacts still closed), an
alarm condition is initiated.

FUNCTION

DESCRIPTION

Controllers

TEMP system Thermostat

Sensor Required

Duct Temperature Sensor

Sensor Wiring

Wires to Terminal 13 and 15

Input

Unit Discharge Air Temperature

Output

SE07 Heat Mode Alarm, SE08 Cool
Mode Alarm