Specifications

Stuck Gas Valve Alarm — Refer to Table 12 for Stuck
Gas Valve Alarm specifications.
Table 12 — Stuck Gas Valve Alarm
FUNCTION DESCRIPTION
Controllers Monitor Thermostat
Sensor Required N/A
Sensor Wiring N/A
Input Duct Temperature Sensor (Damper)
Output SE13, Stuck Gas Valve Alarm
Category/Option None
Configuration
Values
None
Configuration
Increments
None
Associated
Functions
None
OPERATION — The Stuck Gas Valve sequence is used to
allow the system to properly react to a failure mode of the
HVAC unit when the gas valve becomes stuck in the open
position. When this condition exists, the unit is unable to
shut off the heat. To minimize this problem, the internal limit
switch trips causing the indoor fan to turn on and remain on
until the gas is manually shut off and the heat exchanger cools
to normal temperatures.
Without this feature, a VVTt system operating normally
would close each of its zone dampers as space conditions
warmed to set point. This would cause the heated air to be
recirculated back through the unit, further aggravating the
overheating problem. With the Stuck Gas Valve sequence,
the VVT dampers open to their configured Maximum Damper
Position (category 3, option 1). This allows space tempera-
tures in the building to rise to higher than normal tempera-
ture levels. However, this sequence reduces the temperature
buildup in the unit and keeps the heat exchanger operating
within temperatures to prevent failure.
During No System Mode — If the duct temperature rises to
greater than 175 F, the indoor fan is started. The fan will
remain on if that temperature does not drop below 150 F
after 3 minutes. The bypass damper will be closed, and all
zone dampers will open to their maximum position. A Stuck
Gas Valve alarm (SE13) will be initiated.
During a Cooling Mode — If the duct temperature does not
drop below 80 F within 10 minutes, the cooling mode will
be dropped for 10 minutes. The "No System Mode" logic
will test for this condition.
During a Heating Mode — No action is required in this mode.
CONFIGURATION TO ACTIVATE ALARM — No con-
figuration is needed to activate this alarm.
CONFIGURATION TO NORMALIZE ALARM — To re-
move this alarm, follow the procedure to clear the alarm from
the thermostat and network using manual reset.
CLEARING THE ALARM FROM THE THERMOSTAT —
The alarm can be cleared or erased from the system in two
ways:
• Cycle power to the thermostat off, then on.
• Initiate a reset by switching the Unit Reset option to the
ON configuration (category 7, option 11).
NETWORK ACCESSIBLE VARIABLES
When using network access software, the following tables
can be accessed. The variables in the tables can be read, writ-
ten, or forced to a certain value. The monitor thermostat point
display table is shown in Table 13. Other network software
access tables are shown in Table 14.
Table 13 — Monitor Thermostat Point Display Table
VARIABLE
DESCRIPTION
UNIT
DISPLAY
POINT
NAME
READ/WRITE
CAPABILITY
Zone Temperature °F ZT Yes
Duct Temperature °F DT Yes
Outside Air Temperature °F OAT Yes
Zone Demand °F ZDMD Read Only
Demand Type Cool/Heat DMDTYPE Read Only
Controller Set Point °F SETPOINT Read Only
Occupied Yes/No OCC Yes
Damper Position 0-15 DPOS Yes
System Cool Stage 1 On/Off C1 Read Only
System Cool Stage 2 On/Off C21 Read Only
System Heat Stage 1 On/Off H1 Read Only
System Heat Stage 2 On/Off H2 Read Only
System Fan On/Off FN Yes*
Auxiliary Relay On/Off AUX Yes†
System Fan Status On/Off SFANS Read Only
DX Coil Temperature °F DX Yes
Filter Status Clean/Dirty FILS Yes
Monitor System IAQ Status Normal/Alarm IAQLOG Yes
Zone in IAQ Status Yes/No ZONEIAQ Read Only
Any Zone in IAQ Yes/No ANYIAQ Read Only
Indoor Relative Humidity %RHYes
Outdoor Relative Humidity % OARH Read Only
HVAC Usage Meter (Mtr) Minutes UMHVAC Yes
Override (Ovrd) Usage Mtr Minutes UMUO Yes
HVAC Ovrd Usage Mtr Minutes UMUOSM Yes
*Forcing the system fan will cause any energized system stages to turn off.
†If Auxiliary Relay is configured as 0 or 1, then the point can be forced with no
other effect. Other configurations will cause system stages and fan to turn off.
Table 14 — Network Access Tables
TABLE DESCRIPTION TABLE NAME
Points Display Table ZONESTAT
Set Point Table SETPOINT
Config Table 1 CONFIG1
Config Table 2 CONFIG2
Maintenance Table 1 ALARMLOG
Maintenance Table 2 OCCPC01E
Optimal Start Table AOSSDEFC
Service Table 1 SERVICE1
Service Table 2 SERVICE2
Service Table 3 SERVICE3
Alarm POC Table ALARMDEF
Alarm Text Table ALARMS01
Broadcast POC Table BRODEFS
Broadcast Table BROCASTS
Occupancy POC Table OCCDEFM
Occupancy Supervisory Table OCCPC01S
Holiday POC Table HOLIDEF
Holiday Schedule 1 HOLDY01S
Holiday Schedule 2 HOLDY02S
Holiday Schedule 3 HOLDY03S
Holiday Schedule 4 HOLDY04S
Holiday Schedule 5 HOLDY05S
Holiday Schedule 6 HOLDY06S
Holiday Schedule 7 HOLDY07S
Holiday Schedule 8 HOLDY08S
Holiday Schedule 9 HOLDY09S
Holiday Schedule 10 HOLDY10S
Holiday Schedule 11 HOLDY11S
Holiday Schedule 12 HOLDY12S
Holiday Schedule 13 HOLDY13S
Holiday Schedule 14 HOLDY14S
Holiday Schedule 15 HOLDY15S
Holiday Schedule 16 HOLDY16S
Holiday Schedule 17 HOLDY17S
Holiday Schedule 18 HOLDY18S
Time/Date Table TIME
Device ID Table CCS_MON
POC — Product Outboarded Control
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