WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions
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Manual Modes
The following manual modes cannot be scheduled or
triggered remotely. Instead, these manual modes can
only be initiated locally via user interface with the room
thermostat. All parameter-defining rules of each mode
are configurable; see Table 3.
Override Mode
Press the Override button
on the room
thermostat to initiate the Override Mode. The Override
Mode has a limited duration time, set by the room
thermostat configuration parameters. After the Override
Mode expires, the room thermostat returns to its
regularly scheduled mode.
The Override Mode overrides the scheduled Occupied
Mode or Unoccupied Mode by allowing the user to
control the HVAC system through the local thermostat,
and it permits a wider Comfort Zone range. If the room
temperature is outside the Override Comfort Zone
range, the room thermostat disables the local
thermostat controls.
The Override Mode Comfort Zone range and the
Override Mode duration time are set by the room
thermostat configuration parameters; see Table 3.
Shoulder Mode
Press the Shoulder button
on the WT-4000
Series Room Thermostat to initiate the energy saving
transition from the Occupied Mode to the Unoccupied
Mode. While in the Shoulder Mode, the room
thermostat does not call for heating or cooling when the
room temperature is between the upper and lower
Shoulder Mode Comfort Zone temperature limits.
Use the Shoulder Mode to manually set back the room
temperature setpoint if occupants leave the facility
earlier than the scheduled time. Doing so essentially
overrides the current schedule, until the next scheduled
mode change occurs. For example, when the zone is
running a 5-day, 8 A.M. to 6 P.M. occupancy schedule
but one day the occupants are leaving at 2 P.M., the
zone can be manually set into Shoulder Mode at 2 P.M.
The room thermostat remains in Shoulder Mode until
6 P.M., at which time it follows its regular schedule
again.
The upper and lower Shoulder Mode Comfort Zone
temperature limits are set by the room thermostat
configuration parameters; see Table 3.
Note:
The Shoulder Mode can also be used as a
Demand Response Mode, which can be triggered
remotely from the monitoring and control application.
Fail-Safe Features
The WT-4000 Series Pneumatic-to-DDC Room
Thermostats have a number of programmed fail-safe
features that ensure continuous HVAC operation. In the
event of a communication failure with the WT-BAC-IP
Gateway, the wireless network, or the HVAC
equipment, a fail-safe mechanism ensures that the
devices continue to operate in logical fashion. Once the
failure condition no longer exists, the devices recover
from fail-safe mode and resume normal operation.
Loss of Radio Communication with Site Controller
If the room thermostat experiences radio
communication failure with the WT-BAC-IP Gateway,
the room thermostat automatically goes into the
Occupied Mode. When the room thermostat regains
communication with the WT-BAC-IP Gateway, the
room thermostat automatically receives updated mode
status, setpoint values, and other configuration
commands based on the latest user schedule.
Protection Zone
To protect building infrastructure, equipment, and
occupants, the room thermostat has extreme
temperature limits (configurable by the user) that allow
temperatures to float independently from any mode
settings. If these temperature limits are reached, the
room thermostat automatically reacts and adjusts
heating or cooling despite what scheduled mode is
running. The protection zone default value for the
upper temperature limit is 95°F (35°C) and the lower
temperature limit is 40°F (4°C).
