Operation. Johnson Controls WT-4000 0FR, WT-4000 MFR, WT-4000 0CM, WT-4000 MCM, WT-4000 0FM, WT-4000 MFM, WT-4000 0CR, WT-4000 MCR
Below you will find brief information for thermostat WT-4000 MCR, thermostat WT-4000 0CR, thermostat WT-4000 MCM, thermostat WT-4000 0CM, thermostat WT-4000 MFR, thermostat WT-4000 0FR. The instructions are designed to help with the installation process and ensure proper functionality. It provides guidance on mounting, connecting the air lines and setting up the wireless network. This document also covers the operation modes and how to adjust the setpoint temperature for your devices. The WT-4000 series is designed for non-invasive replacement of existing pneumatic thermostats, enhancing energy efficiency and comfort.
Advertisement
Advertisement
Operation
The WT-4000 Series Pneumatic-to-DDC Room
Thermostats are regulated by a number of operational modes that can be triggered by inputs such as changes in inside and outside environments, data received from other sensing devices, and scheduled times. Each mode is designed to optimize energy use under certain conditions, and has a set of rules that manages operation of HVAC equipment and restricts local room thermostat requests.
The two types of operational modes are scheduled and manual. Scheduled modes are triggered by occupancy schedules, and provide energy savings by aligning the operation of HVAC equipment to the actual building occupancy. Manual modes are initiated by the user at the room thermostat level, and adjust the operation of
HVAC equipment manually outside of the schedule, but within set energy policy parameters.
The WT-4000 Series Room Thermostats are designed to support any 0 to 22 psig (0 to 152 kPa) pneumatic
HVAC control system. Variation in branch line pressure is proportional to the deviation of room temperature from the setpoint. The proportional factor is determined by the gain/sensitivity, which is defined as the change in branch line pressure in psi (kPa) in response to a 1F°
(0.6C°) change in room temperature.
Figure 16 illustrates the linear relationship between
branch line pressure and room temperature, at a given setpoint for a Direct Acting (DA) room thermostat configuration. For a Reverse Acting (RA) room thermostat configuration, the graph is inverted horizontally.
Gain/
Sensitivity
Setpoint
Pressure
Half of the
Proportional Band
Set-
Point
Half of the
Proportional Band
Temperature, °F (°C)
1F°
(0.6C°)
Dead Zone
±1F° (±0.6C°)
Figure 16: Branch Line Pressure vs. Room Temperature
WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions 13
In a DA room thermostat configuration, the branch line pressure increases in response to an increase in room temperature. When the room temperature is within the
±1F° (±0.6C°) dead zone around the setpoint, the branch line pressure is regulated at the setpoint pressure, and the pneumatic actuator is at the minimum heat (cool or neutral) position.
When the room temperature rises above the setpoint plus the dead zone, the branch line pressure increases proportionally to the increase in temperature. The proportional factor is defined by the gain/sensitivity value.
When the room temperature decreases below the setpoint minus the dead zone, the branch line pressure decreases proportionally to the decrease in temperature. The proportional band defines the temperature range, where the branch line pressure changes proportionally to the change in temperature.
Note: The setpoint pressure, dead zone, gain/sensitivity, and proportional band are adjusted using the menu buttons on the WT-4000 Series Room
Thermostat.
Wireless Operation
The WT-4000 Series Pneumatic-to-DDC Room
Thermostats include wireless and stand-alone models, designed to monitor and control pneumatic HVAC systems. The room thermostats are equipped with a
2.4 GHz IEEE 802.15.4 radio that communicates via a wireless mesh network. The wireless mesh network forms itself, and data communications enable remote monitoring, adjustment, and trending to provide longer and more dependable and maintenance-free operation.
Note: For each room thermostat in the wireless mesh network, only one object can be written at a time, and the next object cannot be written for at least 5 minutes.
In a wireless mesh network, the room thermostat operates as a battery-powered end node. Being an end node, the room thermostat does not operate as a router to relay data for other devices in the mesh network.
Instead, the room thermostat communicates with the wireless mesh network as an individual device that transmits and receives its own data only, to and from the WT-BAC-IP Gateway or through other
WT-ROUTER Routers.
During wireless operation, an antenna icon appears in the upper-right corner of the LCD when the room thermostat communicates with the wireless mesh
network (Figure 17). The number below the antenna
icon represents the number of devices that the room thermostat can communicate with. It is desirable that the room thermostat have two devices it can communicate with. With two devices, if one communication link fails, then the other communication link can be used without delaying any transmissions.
Figure 17: LCD during Wireless Communication
When the room thermostat is installed in buildings with common sheetrock walls, the nominal radio communication range of the room thermostat is approximately 200 ft (61 m). If the room thermostat is located more than 200 ft (61 m) from the WT-BAC-IP
Gateway, then WT-ROUTER Routers must be installed to relay data generated by the room thermostat back to the WT-BAC-IP Gateway.
14 WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions
Stand-Alone Operation
Stand-Alone Room Thermostat Occupancy
Programming
The WT-4000-0CR, WT-4000-0CM, WT-4000-0FR, and WT-4000-0FM models operate as stand-alone pneumatic-to-DDC room thermostats with an independent time clock, and can be programmed with a Weekday/Weekend occupancy schedule.
During stand-alone operation, a person icon appears in
the upper-right corner of the LCD (Figure 18). When
the room thermostat is powered up for the first time, the number 1024 appears on the bottom of the LCD indicating that the time and date need to be set before the device can operate according to the occupancy schedule.
Figure 18: LCD during Stand-Alone Operation
A complete 7-day schedule consists of two independent components:
• Weekday Schedule – Monday through Friday
• Weekend Schedule – Saturday through Sunday
Each component is split into two parts to be scheduled as Occupied or Unoccupied Mode:
• Weekday 1
• Weekday 2
• Weekend 1
• Weekend 2
Each part can be configured to Occupied or
Unoccupied Mode independently, to accommodate for daytime or nighttime shift schedules.
For each Occupied Mode, the following features can be configured:
• Occupied Mode start time
• Temperature setpoint range – adjustable ±14F°
(±8.4C°) by the room occupants
For each Unoccupied Mode, the following features can be configured:
• Unoccupied Mode start time
• Upper temperature limit
• Lower temperature limit – the room thermostat is off while the room temperature is within these limits
WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions 15
The start time of each schedule part is automatically the end time of the previous schedule part. For example, when the occupied schedule is 6 A.M. to
6 P.M., the Occupied Mode starts at 6 A.M. and the
Unoccupied Mode starts at 6 P.M. Figure 19 and
Figure 20 illustrate the Occupied and Unoccupied
Mode schedule setup.
Occupied or Unoccupied
(Defines the occupancy mode of the part.)
Setpoint Temperature
(Defines the Occupied Mode setpoint temperature of the part.)
Weekday 1
Occupied
07:00
70
Weekday 1, Weekday 2,
Weekend 1, or Weekend 2
(Defines which part is being edited.)
Time in 24-Hour Format
(Defines the start time of the part.)
Figure 19: WT-4000 Series Pneumatic-to-DDC Room Thermostat
Schedule Setup Screen for Occupied Mode
Occupied or Unoccupied
(Defines the occupancy mode of the part.)
Upper Temperature Limit
(Defines the Unoccupied Mode upper temperature limit of the part.)
Weekday 2
Unoccupied
18:00
85 55
Weekday 1, Weekday 2,
Weekend 1, or Weekend 2
(Defines which part is being edited.)
Time in 24-Hour Format
(Defines the start time of the part.)
Lower Temperature Limit
(Defines the Unoccupied Mode lower temperature limit of the part.)
Figure 20: WT-4000 Series Pneumatic-to-DDC Room Thermostat
Schedule Setup Screen for Unoccupied Mode
16 WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions
Stand-Alone Room Thermostat Configuration
To set the time and program the stand-alone room thermostat occupancy schedule and temperature setpoints:
1.
Press and hold the Shoulder button and the
Override button simultaneously for
10 seconds to set the room thermostat in the
Configuration Mode. Initially, the LCD changes to the firmware version screen, and then after
10 seconds the configuration menu appears.
Confirm that the first line in the configuration menu shows Standalone; if it indicates Mesh, switch to
a.
Press the Up button
+
.
3.
Press press
to confirm the selection.
4.
Select Date & Time on the menu (Figure 23) and
to enter the setup screen.
Weekday
Weekend
Figure 23: Selecting Date and Time
5.
In the Date & Time menu (Figure 24), press
to highlight the menu options that require editing. b.
Press to select.
c.
Press the Up button
+
or the Down button
-
to change the value.
d.
Press to confirm the selection.
Year 2014
Minute 01
Figure 24: Setting the Date and Time
Standalone
Net Config
Fan Mode
Standalone
Maintenance
Figure 21: Stand-Alone Menu
2.
Use the Up/Down buttons to select Standalone on
Standalone
Net Config
Fan Mode
Standalone
Maintenance
Figure 22: Selecting the Stand-Alone Mode
6.
Press the Up button
+
or the Down button
-
to change the value.
7.
Press to confirm the selection.
8.
Repeat Step 5 through Step 7 until all of the menu
options are configured correctly. Press the Up button
+
or the Down button
-
to scroll through the date and time menu options.
9.
While in the configuration menu, use the Up/Down buttons to navigate to Weekday to program the weekday schedule.
10. Press to open the weekday schedule.
WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions 17
11. Set the Weekday 1 schedule (Figure 25), which is
usually the start of the Occupied Mode.
Weekday 1
Occupied
07:00
70
Figure 25: Setting the Weekday 1 Schedule
b.
Press c.
Press the Up button
+
or the Down button
-
to change the selection to Weekday 2.
d.
Press
to highlight the selection.
to save the setting.
a.
Leave the top line as Weekday 1.
b.
Press the Up button
+
or the Down button
-
to scroll through the occupancy mode, start time, and lower temperature limit menu items.
c.
Press to open a specific menu item.
e.
Press the Up button
+
or the Down button
-
to scroll through the occupancy mode, start time, upper temperature limit, and lower temperature limit menu items.
f.
Press to open a specific menu item.
d.
Press the Up button
+
or the Down button
-
to change the value, then press save the setting.
12. Set the Weekday 2 schedule (Figure 26).
Weekday 2
Unoccupied
18:00
85 55
Figure 26: Setting the Weekday 2 Schedule
to a.
Press the Up button
+
or the Down button
-
to navigate to Weekday 1.
g.
Press the Up button
+
or the Down button
-
to change the value, then press save the setting.
to
13. While in the configuration menu, use the Up/Down
buttons to navigate to Weekend (Figure 27).
Standalone
Weekday
Weekend
Figure 27: Selecting Weekend
14. Program the weekend schedule in a similar manner as the weekday schedule.
15. Once all programming is complete, press exit the Configuration Mode.
to
18 WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions
Occupancy Programming Example – Standard
Office Hours
• Setpoint: 70°F
• Occupied from 9 A.M. to 5 P.M., Monday through
Friday
• Saturday and Sunday: Unoccupied, Upper Limit is
85°F, Lower Limit is 55°F
Program the WT-4000 Series Room Thermostat
schedule setup screens as illustrated in Figure 28.
Weekday 1
Weekday 2
Weekend 1 Weekend 2
Occupied
Unoccupied Unoccupied
09:00 17:00
09:00*
70
85 55
85
55
85
* The start and end times are irrelevant, since both weekend parts are set to the same unoccupied mode.
17:00*
55
Figure 28: Occupancy Programming Schedule;
Standard Office Hours
Occupancy Programming Example – Night Shift
Hours
• Setpoint: 70°F
• Occupied from 3 P.M. to 6 A.M., Monday through
Sunday
Program the WT-4000 Series Room Thermostat
schedule setup screen as illustrated in Figure 29.
85
06:00
55
70
Occupied
Weekend 1
Unoccupied
06:00
85
55
Figure 29: Occupancy Programming Schedule;
Night Shift Hours
Weekend 2
Occupied
15:00
70
WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions 19
Occupancy Programming Example – Extended
Office Hours with Weekend Schedule
• Setpoint: 70°F
• Occupied from 8 A.M. to 6 P.M., Monday through
Friday
• Occupied from 10 A.M. to 1 P.M., Saturday and
Sunday
Program the WT-4000 Series Room Thermostat
schedule setup screen as illustrated in Figure 30.
Weekday 1
Occupied
08:00
70
Weekday 2
Unoccupied
85
18:00
55
Weekend 1
Occupied
10:00
70
Figure 30: Occupancy Programming Schedule;
Extended Office Hours with Weekend Schedule
Unoccupied
85
13:00
55
Room Thermostat Operational Modes
Scheduled Modes
Scheduled WT-4000 Series Pneumatic-to-DDC Room
Thermostat operational modes are regulated by the
HVAC schedules, as defined by the user. The HVAC schedules can be set in advance through the building automation system for wireless communicating models, and locally at each room thermostat for stand-alone models. The room thermostat executes the
HVAC schedules automatically.
Occupied Mode
Use the Occupied Mode when the room is scheduled to be occupied. During the Occupied Mode, the room temperature is defined by two values set by the room thermostat configuration parameters:
• Setpoint – the targeted room temperature for the season
• Comfort Zone – the optimal temperature range around the setpoint
The room thermostat maintains the room temperature within the Comfort Zone. If the room temperature falls outside of the range of the Comfort Zone, the room thermostat reacts accordingly and automatically requests heating or cooling.
The room thermostat allows users to adjust the room temperature using the local room thermostat, as long as the desired room temperature is within the range of the Comfort Zone. If the user requests heating or cooling outside of the range of the Comfort Zone, the request at the local room thermostat is overwritten by the room thermostat configuration parameters.
Example: The setpoint temperature is 70°F (21°C) and the range of the Comfort Zone is ±3F° (±1.8C°) around the setpoint temperature. The user is manually able to affect the room temperature only between 67 and 73°F
(19 and 23°C), regardless of the temperature requested on the LCD of the local room thermostat.
Stand-alone room thermostats do not feature a configurable Comfort Zone. Instead, stand-alone models have a factory set range of ±14F° (±8.4C°) around the installer-configured setpoint temperature in the Occupied Mode.
Unoccupied Mode
Use the Unoccupied Mode to save energy during those times when a room is unoccupied. The room thermostat does not call for heating or cooling when the room temperature is within the upper and lower
Unoccupied Mode temperature limits. If the room temperature falls outside of the upper and lower
Unoccupied Mode temperature limits, the room thermostat calls for heating or cooling to bring the room temperature back within the Unoccupied Mode upper and lower temperature limits.
20 WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions
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).
WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions 21
WT-4000 Series Pneumatic-to-DDC Room
Thermostat Configuration Parameters
The variables included in Table 3 define the
WT-4000 Series Pneumatic-to-DDC Room Thermostat configuration parameters and regulate room thermostat operation.
Table 3: WT-4000 Series Room Thermostat Configuration Parameters (Part 1 of 2)
Parameter Description Configuration
Method
Occupied Mode
Setpoint value
Comfort Zone upper delta; default = 14F° (8.4C°)
Comfort Zone lower delta; default = 14F° (8.4C°)
Unoccupied Mode
Constrained float upper limit; default = 85°F (29°C)
Constrained float lower limit; default = 55°F (13°C)
Zone setpoint temperature
Upper temperature bound on deviation from configuration parameters setpoint during Occupied Mode
Lower temperature bound on deviation from parameter setpoint during Occupied Mode
Configuration tool
Configuration tool
Configuration tool
Defines upper temperature limit in Unoccupied Mode;
HVAC equipment remains off while the zone temperature is between the upper and lower limits
Defines lower temperature limit in Unoccupied Mode;
HVAC equipment remains off while zone temperature is between the upper and lower limits
Configuration tool
Configuration tool
Override Mode
Override duration; default = 120 minutes
Room thermostat override duration (240 minute maximum duration); after time limit expires, room thermostat goes into regularly scheduled mode
Comfort Zone upper delta during Override Mode
Configuration tool
Configuration tool Override Mode
Comfort Zone upper delta; default = 14F° (8.4C°)
Override Mode
Comfort Zone lower delta; default = 14F° (8.4C°)
Other Parameters
Network configuration
(Net Config)
Comfort Zone lower delta during override Mode Configuration tool
Operational modes
Dead zone delta; default = 1F° (0.6C°)
Room thermostat protection zone – upper limit; default = 95°F (35°C)
Room thermostat protection zone – lower limit; default = 40°F (4°C)
Default Occupied Mode start time in the event of wireless communication failure; default = 06:00 A.M.
CH: To change the radio channel number; default = 11
GI: To change the device network group ID; default = 111.111
DI: To change the unique thermostat device ID; default = 71.40
1: Occupied
2: Unoccupied
Temperature range around setpoint, to prevent HVAC from chattering
Maximum temperature allowed in zone; fail-safe feature applicable to all zones
Configuration tool, room thermostat
Factory configured
Configuration tool
Factory configured
Minimum temperature allowed in zone; fail-safe feature applicable to all zones
Time of day (0 to 24 hours) in the event the room thermostat goes offline for an extended duration
Factory configured
Factory configured
22 WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions
Table 3: WT-4000 Series Room Thermostat Configuration Parameters (Part 2 of 2)
Parameter Description Configuration
Method
Factory configured Default Occupied Mode setpoint value in the event of wireless communication failure; default = 70°F (21°C)
Default Unoccupied Mode setpoint start time in the event of wireless communication failure
Temperature sensor calibration factor; °F (°C)
Shoulder Mode Comfort Zone upper delta
Shoulder Mode Comfort Zone lower delta
Direction
Temperature used in the event the room thermostat goes offline for an extended duration
Time of day (0 to 24 hours) in the event the room thermostat goes offline for an extended duration; disabled in default configuration; therefore, device does not go into Unoccupied
Mode when offline
Calibrates the room thermostat temperature sensor for offset compensation
Defines upper temperature limit in Shoulder Mode
Defines lower temperature limit in Shoulder Mode
Setpoint psig
Gain/sensitivity
Proportional band – proportional range/throttling range
Unoccupied Mode psig
Direct acting – branch line pressure increase turns on cooling; decrease turns on heating
Reverse acting – branch line pressure increase turns on heating; decrease turns on cooling
Branch line pressure when room temperature and setpoint are equal (no heating or cooling outputs)
Branch line pressure change needed to change the room temperature by 1F° (0.6C°)
Temperature range that represents the controlled device’s movement from fully closed to fully open; typically 4F° (2.4C°) or 6F° (3.6C°)
Branch line pressure during Unoccupied Mode when zone temperature is within unoccupied constrained upper and lower limits
Factory configured
Factory configured
Configuration tool
Configuration tool
Configuration tool, room thermostat
Configuration tool, room thermostat
Configuration tool, room thermostat
Configuration tool, room thermostat
Configuration tool, room thermostat
WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions 23
Table 4: WT-4000 Series Room Thermostat Point Mapping (Part 1 of 3)
Object Name
1 Description BACnet®
Type
Read/Write or
Read-Only
More Information
WT_4000_xxx_av_5
WT_4000_xxx_av_7
WT_4000_xxx_av_8
WT_4000_xxx_av_9
WT_4000_xxx_av_10
WT_4000_xxx_av_11
WT_4000_xxx_av_12
WT_4000_xxx_av_13
WT_4000_xxx_av_14
WT_4000_xxx_av_15
WT_4000_xxx_av_16
WT_4000_xxx_av_18
WT_4000_xxx_av_31_Byte_H
WT_4000_xxx_av_31_Byte_L
Mode = 1-Occ:
2-Unocc: 7-Shoulder
Comfort upper delta
Comfort lower delta
Heat/Cool delta
Constrained upper delta
Constrained lower delta
Maximum protection temperature
Minimum protection temperature
Override timer maximum
Override upper delta
Override lower delta
Heat/Cool dead zone delta
Setback upper delta
Setback lower delta
AV
AV
AV
AV
AV
AV
AV
AV
AV
AV
AV
AV
AV
AV
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
Read/write
Mode being requested by schedule
1 = Occupied
2 = Constrained float (Unoccupied)
3 to 6: Reserved
7 = Shoulder Mode (shallow setback, also used
in demand response events)
The value represents delta value in °F (°C) multiplied by 10 (BACnet object shows actual value); default 3°F (1.8°C); maximum comfort zone is 14°F (8.4°C)
The value represents delta value in °F (°C) multiplied by 10 (BACnet object shows actual value); default 3°F (1.8°C); maximum comfort zone is 14°F (8.4°C)
Temperature delta in °F (°C) multiplied by 10 before transitioning from heating to cooling or cooling to heating (BACnet object shows actual value); default 0°F (0°C)
Default Unoccupied Mode; defines the upper temperature limit in constrained Unoccupied
Mode; value represents limit in °F (°C) multiplied by 10 (BACnet object shows actual value); default 85°F (29°C)
Default Unoccupied Mode; defines the lower temperature limit in constrained Unoccupied
Mode; value represents limit in °F (°C) multiplied by 10 (BACnet object shows actual value); default 55°F (13°C)
Maximum temperature allowed in zone multiplied by 10 (BACnet object shows actual value); default 95°F (35°C)
Minimum temperature allowed in zone multiplied by 10 (BACnet object shows actual value); default 40°F (4°C)
Maximum 240 minutes; in increments of
1 minute
Comfort Zone upper delta during Override Mode, in °F multiplied by 10 (BACnet object shows actual value); default 5°F (3°C)
Comfort Zone lower delta during Override Mode, in °F (°C) multiplied by 10 (BACnet object shows actual value); default 5°F (3°C)
Temperature control dead zone in °F (°C) multiplied by 10 (BACnet object shows actual value); default 1°F (0.6°C)
Shoulder Mode is used for shallow setback (as opposed to constrained float for deep setback); it is also the mode used in a demand response event; high byte indicates upper delta, in °F (°C) multiplied by 10, relative to setpoint (BACnet object shows actual value); device does not call for cooling if room temperature is below setpoint plus upper delta in Shoulder Mode
Low byte indicates lower delta, in °F (°C) multiplied by 10, relative to setpoint (BACnet object shows actual value); device does not call for heating if room temperature is above setpoint minus lower delta
24 WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions
Table 4: WT-4000 Series Room Thermostat Point Mapping (Part 2 of 3)
Object Name
1 Description BACnet®
Type
Read/Write or
Read-Only
More Information
WT_4000_xxx_av_33
WT_4000_xxx_ai_54
Display mode AV
AI
Read/write
Read-only
0 = Normal LCD and button functionality
1 = No temperature display; buttons are disabled
2 = Normal LCD functionality; buttons are
disabled
Note:
Display mode set to any other value results in normal LCD and button functionality; this feature is not supported for stand-alone models.
High 16 bits of 32 bit UTC time (UNIX epoch time)
WT_4000_xxx_ai_55
WT_4000_xxx_ai_57
High 16 bits of standard 32 bits
UTC time
Low 16 bits of standard 32 bits
UTC time
Zone temperature
AI
AI
Read-only
Read-only
Low 16 bits of 32 bit UTC time
WT_4000_xxx_ai_58_Byte_H
WT_4000_xxx_ai_58_Byte_L
WT_4000_xxx_bi_59_Bit_0
WT_4000_xxx_bi_59_Bit_1
WT_4000_xxx_bi_59_Bit_6
Branch line pressure requested
Branch line pressure measured
Heating status
Cooling status
AI
AI
BI
BI
BI
Read-only
Read-only
Read-only
Read-only
Read-only
Temperature value in degree F multiplied by 10
(BACnet object shows actual value)
High byte indicates pressure requested by the unit based on temperature measurement, in psig
(kPa) multiplied by 10 (BACnet object shows actual value)
Low byte represents actual branch line pressure measured by the pressure sensor, in psig (kPa) multiplied by 10 (BACnet object shows actual value)
Active = heating on (branch line pressure in
heating zone)
Active = cooling on (branch line pressure in
cooling zone)
Active = Override Mode button pressed
WT_4000_xxx_bi_59_Bit_7
WT_4000_xxx_bi_59_Bit_10
Override button pressed
Setback button pressed
Occupancy sensor
Shoulder Mode
BI
BI
Read-only
Read-only
Active = Shoulder Mode button pressed
WT_4000_xxx_ai_60
WT_4000_xxx_av_61
WT_4000_xxx_ai_62
WT_4000_xxx_av_69
WT_4000_xxx_av_70_Byte_H
Mode = 1-Occ:
2-Unocc: 7-Shoulder
Zone temperature setpoint - system
Zone temperature setpoint - user
Setpoint pressure
Action direction
AI
AV
AI
AV
AV
Read-only
Read/write
Read-only
Read/write
Read/write
Active = in Shoulder Setback Mode (no motion
detected for 30 minutes)
Inactive = in Occupied Mode
Note:
Supply air must be provided to the room thermostat for this feature to be functional.
This register represents the mode that the unit is currently in.
1 = Occupied
2 = Constrained float (Unoccupied)
3 to 6: Reserved
7 = Shoulder Mode
This register represents setpoint specified by energy management application, in °F (°C) multiplied by 10 (BACnet object shows actual value); default 70°F (21°C)
This register represents setpoint specified by pressing Up/Down buttons on the unit, in °F (°C) multiplied by 10 (BACnet object shows actual value); default 70°F (21°C)
The pressure when temperature is at setpoint value, in psig (kPa) multiplied by 10 (BACnet object shows actual value); valid range 1 to
22 psig (7 to 152 kPa); default 9 psig (62 kPa)
High byte shows action direction:
0 = direct acting (default)
1 = reverse acting
WT-4000 Series Pneumatic-to-Direct Digital Control (DDC) Room Thermostats Installation Instructions 25

Public link updated
The public link to your chat has been updated.
Advertisement
Key features
- Wireless mesh network communications
- Remote temperature setpoint control
- Occupancy scheduling
- Continuous room temperature, branch line pressure, and battery status monitoring
- Non-invasive replacement of existing pneumatic thermostats
- Solid state temperature sensor
- Advanced piezoelectric air valve
- Stand-alone operation
- Occupancy sensor input