Fan Switch; Fan Operation For Heat; Zone Caller; System Mode - Carrier 33CS Installation, Service, And Troubleshooting Instructions

To control the cool switch setting, configure category 4,
option 19. These range is from 0 to 2. When the option is set to
0, the thermostat will use the setting of the mechanical cool
switch. When the option is set to 1, the thermostat will perform
as if the cool switch is set to AUTO (regardless of the mechan-
ical cool switch setting). When the option is set to 2, the ther-
mostat will perform is if the cool switch is set to OFF (regard-
less of the mechanical cool switch setting). The setting of 0, is
the default setting.
Fan Switch —
The fan switch is located on the bottom of
the TEMP system thermostat. The fan switch controls the sys-
tem fan operation. See Fig. 11.
When the fan switch is set to ON, the TEMP system ther-
mostat energizes the fan relay continuously when the TEMP
system thermostat is in occupied mode. The fan does not oper-
ate in unoccupied mode.
NOTE: When the TEMP system thermostat is in unoccupied
override mode, the fan operates as if it is in occupied mode.
When the fan switch is set to AUTO, the TEMP system
thermostat energizes the fan relay only during the system heat-
ing or system cooling modes.
To control the fan switch setting, configure category 4,
option 18. These range is from 0 to 2. When the option is set to
0, the thermostat will use the setting of its mechanical fan
switch. When the option is set to 1, the thermostat will perform
as if the fan switch is set to ON (regardless of the mechanical
fan switch setting). When the option is set to 2, the thermostat
will perform is if the fan switch is set to AUTO (regardless of
the mechanical fan switch setting). The setting of 0 is the de-
fault setting.
Fan Operation For Heat —
For Heat option is set to OFF and the fan switch is set to
AUTO, the fan relay is energized by the TEMP system thermo-
stat only during a system cooling mode. During a system heat-
ing mode, the heating/cooling equipment is responsible for fan
operation.
When the Fan Operation For Heat option is set to ON and
the fan switch is set to AUTO, the fan relay is energized by the
TEMP system thermostat during system heating and cooling
modes.
To configure the Fan Operation For Heat option, set catego-
ry 4, option 1. Use the left set point buttons to toggle the option
ON and OFF.
Zone Caller —
If the TEMP system thermostat has suffi-
cient zone demand to energize the heating/cooling equipment,
it is a zone caller. A zone cooling caller has a demand of 1.5° F
or greater for cooling. A zone heating caller has a demand of
1.5° F or greater for heating.
System Mode —
System mode is the operation configu-
ration the TEMP system thermostat uses to determine the oper-
ation of the system and heating/cooling.
For a TEMP system, the TEMP system thermostat checks
its own zone demand. If the TEMP system thermostat is a cool-
ing caller, system cooling mode is selected. If the TEMP sys-
tem thermostat is a heating caller, system heating mode is se-
lected.
The TEMP system thermostat releases a system heating or
cooling mode when:
• the zone demand is satisfied to 0.5° F.
• both first and second stage heating or cooling temperature
limits are exceeded when the zone is no longer a zone caller.
When the Fan Operation
• the Heating or Cooling Temperature Lockouts option is set
to ON and the outside-air temperature exceeds the lockout
temperature set point.
Equipment Operation —
stat operation of the heating, cooling, and reversing valve re-
lays is determined by the zone demand. The Auxiliary Relay
option configures the TEMP system thermostat for equipment
operation.
During a system mode, a stage of heating or cooling cannot
be energized in less than 3 minutes after the previous stage has
been energized. Once a heating or cooling stage has been ener-
gized, it remains on until system heating or cooling mode is re-
leased or trips due to a limit being exceeded. The reversing
valve relay, energized or deenergized, remains constant until a
change of system modes.
AUXILIARY RELAY — The Auxiliary Relay option config-
ures the way the auxiliary relay will be controlled by the
TEMP system thermostat. When the option is set to 0, the
TEMP system thermostat will not control the auxiliary relay.
When the option is set to 1, the TEMP system thermostat will
control the auxiliary relay based on the occupancy schedule.
When the option is set to 2, the TEMP system thermostat will
control the auxiliary relay under IAQ control. When the option
is set to 3, the TEMP system thermostat will control the auxil-
iary relay as a reversing valve in a heat pump system based on
system heating or cooling modes. When the option is set to 4,
the TEMP system thermostat will control the auxiliary relay to
enable or disable economizer control. The Auxiliary Relay
option is set in category 4, option 9. The default is 0.
EQUIPMENT OPERATION DURING A SYSTEM COOL-
ING MODE — The TEMP system thermostat utilizes the
relay pack to energize the reversing valve relay (if option 4.9 is
set to 3) when the system cooling mode is selected. The first
stage of cooling is energized 30 seconds after system cooling
mode is selected. When the reference zone cooling demand is
2.0° F or greater, the second stage of cooling is energized or
optimized staging is followed. The second stage of cooling is
released when demand drops below 1.0° F. The first stage of
cooling is deenergized when the system cooling mode is
released.
EQUIPMENT OPERATION DURING A SYSTEM HEAT-
ING MODE — The TEMP system thermostat utilizes the
relay pack to deenergize the reversing valve relay (if option 4.9
is set to 3) when the system heating mode is selected. The first
stage of heating is energized 30 seconds after system heating
mode is selected. When the reference zone heating demand is
2.0° F or greater, the second stage of heating is energized or
optimized staging is followed. The second stage of heating is
released when demand drops below 1.0° F. The first stage of
heating is deenergized when the system heating mode is
released.
Equipment Operation With Economizer Con-
trol —
The TEMP system thermostat operation of the heat-
ing, cooling, and economizer relays is determined by the sys-
tem mode, the reference zone demand, and the outdoor-air
temperature. The Auxiliary Relay option must be set to 4 to
configure the TEMP system thermostat for equipment opera-
tion with economizer control.
During a system mode, a stage of heating or cooling cannot
be energized in less than 3 minutes after the previous stage has
been energized. Once a heating or cooling stage has been ener-
gized, it remains on until system heating or cooling mode is
released.
16
The TEMP system thermo-