Tekmar D538 User manual

tekmarNet®4 Thermostat 538
Installation & Operation Manual
D538
12/11
Zoning Replaces:08/10
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The tekmarNet®4 Thermostat 538
provides operation for:
One Stage Heat•
Introduction
Features
Zone Synchronization
Zone Post Purge
Intelligent setback (Timer 033)
Scenes (Away override)
Auto Heating Cycle
tekmarNet®4 communication
compatible
Requires 4 wires
Pulse Width Modulation
CSA C US Approved for use in
USA and Canada
Outdoor temperature display
Air Group member
Backlight
Freeze Protection
Equipment Exercising
Floor warming (Slab Sensor 079)
1 Auxiliary sensor input
Room Temperature Limiting
Supports Radiant Floor Cooling
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Congratulations on the purchase of your new tekmar thermostat.
This manual will step through the complete installation, programming and sequence
of operation for this control. At the back, there are tips for control and system
troubleshooting.
Getting Started
Preparation
tekmar or jeweller screwdriver
Phillips head screwdriver
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Wire Stripper•
Tools Required
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Materials Required
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2, #6 x 1” Wood Screws
18 AWG LVT Solid Wire
(Low Voltage Connections)
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Optional Adapter Plate 007 (for
installation on 2” x 4” gang box)
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Installation
Table of Contents
Getting Started ..............................2
Installation .........................................2
Caution..........................................2
Preparation....................................2
Removing The Thermostat Base...3
Mounting The Thermostat Base....3
Thermostat Wiring.........................4
Testing the Thermostat Wiring ......4
Mounting the Thermostat ..............5
Cleaning the Thermostat...............6
Switch Settings ..................................6
User Interface....................................7
Display...........................................7
Button Operation ...........................7
Symbols Description .....................7
Settings ....................................8-14
Sequence of Operation....................15
Heating Operation .......................15
Air Group Operation ....................16
Floor Cooling...............................16
Schedules ................................... 17
Scenes (System Override) .......... 17
Troubleshooting ...............................18
Error Messages......................18-21
Frequently Asked Questions .......22
Job Record..................................23
Technical Data.............................23
Limited Warranty and Product
Return Procedure ........................24
Caution
Improper installation and operation of this control could result in damage to the
equipment and possibly even personal injury or death. It is your responsibility
to ensure that this control is safely installed according to all applicable codes and
standards. This electronic control is not intended for use as a primary limit control.
Other controls that are intended and certified as safety limits must be placed into
the control circuit.

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Choose the placement of the thermostats early in the construction process to
enable proper wiring during rough-in.
Consider the following:
Interior Wall.
Keep dry. Avoid potential leakage onto the control.
Relative Humidity max 92% up to 104°F (40°C), 50% RH above 104°F (40°C).
Non-condensing environment.
No exposure to extreme temperatures beyond 32-122°F (0-50°C).
No draft, direct sun, or other cause for inaccurate temperature readings.
Away from equipment, appliances, or other sources of electrical interference.
Easy access for wiring, viewing, and adjusting the display screen.
Approximately 5 feet (1.5 m) off the finished floor.
The maximum length of wire is 500 feet (150 m).
Strip wire to 3/8” (10 mm) for all terminal connections.
Use standard 4 conductor, 18 AWG wire.
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Installation Location
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Removing The Thermostat Base
Push
tab
1Remove thermostat
from base
2
To remove the thermostat base:
Place a small slot screwdriver or similar
tool into the slot located on the top of
the thermostat.
While pushing down against the plastic
tab, pull the thermostat away from the
thermostat’s base.
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Mounting The Thermostat Base
Stud
Switch
Box
Thermostat
Base
007 Adaptor
Plate
31/4”
(83 mm)
If a single gang switch box is used,
an Adaptor Plate 007 is required to
mount the thermostat to the box.
Fasten the base of the
thermostat to the adaptor plate.
Feed the wiring through the
openings in the back of the
adaptor plate and thermostat.
Use the upper and lower screw
holes to fasten the adaptor plate
to the box.
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Mounted on switch box

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If a switch box was not used, mount the
thermostat directly to the wall.
Feed the wiring through the openings in
the back of the thermostat.
Use screws in the screw holes to fasten the
thermostat to the wall. At least one of the
screws should enter a wall stud or similar
rigid material.
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Stud
23/8”
(60 mm)
screwhole
23/8”
(60 mm)
screwhole
Thermostat
Base
Wall
Mounted on wallboard
Thermostat Wiring
The thermostat operates a single heating system zone.
Connect tN4, C, R, and W terminals on the thermostat to the tN4, C, R, and W
terminals on the tN4 Wiring Center or Zone Manager.
Connect the optional auxiliary sensor wires to the sensor terminals 5 and 6.
12 34
tN4 Wiring Center
or
tN4 Zone Manager
Slab Sensor 072, 073, 079
OR
Outdoor Sensor 070
OR
Indoor Sensor 076, 077, 084
tN4 C W
R
1234
tNt 538
538
One Stage Heat
Mmm YYYY Lot # 12345
Meets Class B: Canadian ICES FCC Part 15
Power: 24 V ±10% 50/60 Hz 1.8 VA
56 VA fully loaded
Relay: 24 V (ac) 2 A
1001-03
tN4
1
C
2
R
3
W
4
65
Sensor
Switch Settings:
For instructions see brochure
Use at least 75°C conductors
Setback
Scene
Lock Not used
ON
Not used Unlock
Off
Off
No Power
Testing the Thermostat Wiring
Testing the Power
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---------------------------------------------------
1. Remove the front cover from the thermostat.
2. Use an electrical test meter to measure (ac) voltage between the R and C
terminals. The reading should be 24 V (ac) +/– 10%.
3. Install the front cover.

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Mounting the Thermostat
To place the thermostat back on the
mounting base:
Place thermostat bottom tabs on
matching mounting base notches.
Pivot top of the thermostat
towards wall, ensuring wires clear
obstructions.
The top clasp makes a clicking
sound when properly closed.
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Pivot
Tab
Testing the Heat Relay
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1. Remove the front cover from the thermostat.
2. Press the button and set the heating temperature below the current room
temperature. There should be no H1 symbol on the display.
3. Set the electrical test meter to continuity.
4. Place probes between R (3) and W (4). There should be no continuity. If there
is continuity then there may be a wiring fault or the relay may be faulty.
5. Press the button and set the heating temperature above the current room
temperature. Make sure the display does not show “WWSD”. The “H1” symbol
should appear on the display.
6. There should be continuity between the R (3) and W (4) terminals.
Testing the tekmarNet®4 Bus
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The symbol is shown on the display when communication is present. If the
thermostat is connected in a network and the communication is missing, there may
be an open or short circuit on the tN4 and C bus wires.
1. Remove the front cover from the thermostat.
2. To test for short circuits:
Disconnect the tN4 bus wires on one end.
Install wire nuts on each wire to ensure the wire ends are not touching.
Disconnect the tN4 bus wires on the other end.
Measure for continuity using an electrical meter.
If continuity is present, there is a short circuit fault along the wires. It is
recommended to replace the tN4 bus wires.
3. To test for open circuits:
Disconnect the tN4 bus wires on one end and connect them together.
Disconnect the tN4 bus wires on the other end.
Use an electrical meter to measure for continuity.
If there is no continuity, there is an open circuit fault along the wires. It is
recommended to replace the tN4 bus wires.
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Switch Settings
Switches are set to “On”
position from the factory, and
do not require changing for
most applications.
12 34
1234
tNt 538
538
One Stage Heat
Mmm YYYY Lot # 12345
Meets Class B: Canadian ICES FCC Part 15
Power: 24 V ±10% 50/60 Hz 1.8 VA
56 VA fully loaded
Relay: 24 V (ac) 2 A
1001-03
tN4
1
C
2
R
3
W
4
65
Sensor
Switch Settings:
For instructions see brochure
Use at least 75°C conductors
Setback
Scene
Lock
Not used
ON
Not used Unlock
Off
Off
No Power
12 34
1234
Mmm YYY L t # 1234
Meets Class B: Canadian ICES
y
2 A
Switch Settings:
Setback
Scene
Lock
Not used
ON
Not used Unlock
Off
Off
Switch Position Action
1
ON
SETBACK
The thermostat follows a programmable setback schedule
as a schedule member if available. Requires the installation
of a Timer 033 to use this feature.
OFF
OFF
The thermostat does not follow a programmable setback
schedule.
2
ON
SCENE
The thermostat responds to changes in the scene (system
wide manual overrides). Requires the installation of a User
Switch 479 to use this feature.
OFF OFF
The thermostat does not respond to scenes.
3
ON
LOCK ACCESS LEVEL
Locked to ‘User’ access level. Set to Lock when installation
completed.
OFF
UNLOCK ACCESS LEVEL
Unlock to allow ‘User’ and “Installer’ access level. Set to
Unlock during installation process.
tekmarNet®reset control must also be set to Unlocked
(Installer access level).
4
ON Not used
OFF Not used
The thermostats’s exterior can be cleaned using a damp cloth. Moisten the cloth
with water and wring out prior to wiping the control. Do not use solvents or cleaning
solutions.
Cleaning the Thermostat

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SECONDARY DISPLAYMAIN DISPLAY
HEAT
Heat is turned on.
SUN
Operating at the occupied
(day) temperature.
MOON
Operating at the unoccupied
(night) temperature.
AWAY
Operating at the Away scene
temperature.
AIR GROUP
The air group is cooling.
Heating can start once the
cooling is finished.
LOCK
Locked to ‘User’ access level.
CLOCK
Operating on a
programmable schedule.
tekmarNet®
Communication is present.
WARNING SYMBOL
Indicates an error is present.
WARM WEATHER SHUT
DOWN
The heating system has been
shut off for the summer.
Display
Symbols Description
User Interface
Button Operation
Press the or the button to select the room temperature.

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Settings (1 of 7)
Display Range Access Description Set to
40 to 95°F
(4.5 to 35.0°C)
Default = 70°F
(21.0°C)
Installer User
SET ROOM HEAT Set the room heating temperature while in the event.
40 to 95°F
(4.5 to 35.0°C)
Default = 65°F
(18.5°C)
Installer User
SET ROOM HEAT Set the room heating temperature while in the event.
40 to 95°F
(4.5 to 35.0°C)
Default = 62°F
(16.5°C)
Installer
SET ROOM HEAT AWAY Set the room heating temperature while in the Away scene.
Continued on next page.
• Press and hold down both the and buttons for 2 seconds to change from one step to the next. • Release both buttons once the step has been reached. • Press the or the button to change the setting, if available. • Press and hold down both the and buttons for 2 seconds to go to the next step, OR • After 10 seconds of no button activity, the display goes back to normal operation. • Note: Set switch setting #3 and tekmarNet®system control to Unlock to change Access level to Installer.
Press
+
Together

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Settings (2 of 7)
Display Range Access Description Set to
40 to 122°F
(4.5 to 50.0°C)
Default = 72°F
(22.0°C)
Installer User
SET FLOOR HEAT Set the floor heating temperature while in the event. Available when:
A slab sensor is installed on the auxiliary sensor input AND Sensor setting in the Adjust menu is set to Floor AND Room Sensor setting in the Adjust menu is set to Off.
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40 to 122°F
(4.5 to 50.0°C)
Default = 65°F
(18.5°C)
Installer User
SET FLOOR HEAT Set the floor heating temperature while in the event. Available when:
A slab sensor is installed on the auxiliary sensor input AND Sensor setting in the Adjust menu is set to Floor AND Room Sensor setting in the Adjust menu is set to Off.
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Off, 30 sec, On,
On +
Default = 30 sec
Installer User
BACKLIGHT Select the backlight operation. Off = Permanently Off 30 = Temporary on for 30 seconds On = Permanently On On + = On during and off during
Continued on next page.

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Display Range Access Description Set to
°F or °C
Default = °F
Installer User
TEMPERATURE UNITS Press the or the button to change from °F to °C and vice versa.
Device Type with
Software Version,
Address
Installer User
DEVICE TYPE Display alternates between the Device Type (large number) with Software Version (upper right corner) and the thermostat address.
40 to 95°F
(4.5 to 35.0°C)
Default = 85°F
(29.5°C)
Installer
MAXIMUM SET ROOM HEAT Set the maximum room heating limit while in the event.
40 to 95°F
(4.5 to 35.0°C)
Default = 85°F
(29.5°C)
Installer
MAXIMUM SET ROOM HEAT Set the maximum room heating limit while in the event.
40 to 95°F
(4.5 to 35.0°C)
Default = 45°F
(7.0°C)
Installer MINIMUM SET ROOM HEAT
Set the minimum room heating limit.
Settings (3 of 7)
Continued on next page.

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Display Range Access Description Set to
Off, 40 to 122°F
(Off, 4.5 to
50.0°C)
Default = 72°F
(22.0°C)
Installer
User
SET FLOOR MINIMUM Set the floor minimum temperature while in the event. The floor minimum heats the floor even when the room temperature is satisfied. The measured floor temperature is shown in the upper right hand corner of the display. Available when:
Room Sensor setting in the Adjust menu is set to On AND A slab sensor is installed on the auxiliary sensor input AND Sensor setting in the Adjust menu is set to Floor.
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Off, 40 to 122°F
(Off, 4.5 to
50.0°C)
Default = Off
Installer
User
SET FLOOR MINIMUM Set the floor minimum temperature while in the event. The floor minimum heats the floor even when the room temperature is satisfied. The measured floor temperature is shown in the upper right hand corner of the display. Available when:
Room Sensor setting in the Adjust menu is set to On AND A slab sensor is installed on the auxiliary sensor input AND Sensor setting in the Adjust menu is set to Floor.
• • •
Settings (4 of 7)
Continued on next page.

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Display Range Access Description Set to
40 to 122°F, Off
(4.5 to 50.0°C,
Off)
Default = 85°F
(29.5°C)
Installer
FLOOR MAXIMUM Set the floor maximum temperature in order to protect the floor covering. Available when:
Room Sensor setting in the Adjust menu is set to On AND A slab sensor is installed on the auxiliary sensor input AND Sensor setting in the Adjust menu is set to Floor.
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1, 2, 3, 4
Default = 1 Installer
SCHEDULE Thermostat can follow schedule master 1, 2, 3, or 4. Available when:
Switch setting 1 is set to Setback (On Position).•
H1
H1
ADJUST
ADJUST
SUPPLY
OFF or On
Default = On Installer
HEAT SUPPLY PUMP During heating, select whether or not the system supply pump should turn on or be off to allow a zone group pump per manifold. Available when:
A reset control is present on the tekmarNet®system.•
Settings (5 of 7)
Continued on next page.

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Display Range Access Description Set to
H1
H1
ADJUST
ADJUST
SUPPLY
OFF or On
Default = OFF Installer
HEAT SUPPLY PUMP DELAY During heating, select whether or not the system supply pump should be delayed by 3 minutes before coming on (for thermal motor or wax actuator). Available when:
A reset control is present on the tekmarNet®system.•
Auto,
SYn(Synchronize)
Default =
Sychronize
Installer
HEAT CYCLES PER HOUR Select either Auto cycle or Synchronize with other thermostats on the tekmarNet®system. Choose Synchronize when zone heated using a boiler. Choose Auto when zone is non-hydronic heating. Available when:
No reset control on the tekmarNet®system.•
ADJUST
ADJUST
OFF, 1 to 16 Installer
AIR GROUP Select if this thermostat should be an air group member. Select off if the thermsotat is not an air group member. Select 1 though 16 to select the air group number. Available when:
The thermostat is connected to other thermostats using tekmarNet®.
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On or Off
Default = On Installer
ROOM SENSOR Select whether the built-in air temperature sensor is on or off. Available when: A floor sensor or room sensor is installed on the auxiliary sensor input.
Settings (6 of 7)
Continued on next page.

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Display Range Access Description Set to
Off, Room,
Outdoor, Floor,
Floor dSP
Installer
AUXILIARY SENSOR Select the type of auxiliary sensor. Off = no auxiliary sensor, Room = Indoor Sensor, Outdoor = Outdoor Sensor, Floor = Slab Sensor, Floor dSP = Floor sensor reading in upper number field. Available when: Auxiliary sensor automatically detected.
01 to 24
(no reset control),
b:01 to b:24
(reset control - boiler),
1:01 to 1:24
(reset control - mixing)
Installer
tekmarNet®ADDRESS The address is shown in the large number field. “Auto” is shown in the upper number field when using automatic addressing. Press the or the button to manually select an address. The address can be returned to automatic “Auto” addressing when address set above 24.
FLOOR
ADJUST
ADJUST
COOL OFF or On
Default = OFF Installer
FLOOR COOLING Select if the thermostat should operate the heating relay W for radiant floor cooling. Available when:
Connected to a tekmarNet®heat pump or chiller system control.
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None Installer
User
ESCAPE Press the or the button to return to normal operation.
Settings (7 of 7)

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Heating Operation Section A
Sequence of Operation
When using only a room temperature sensor, the thermostat operates the heating
system to maintain the Set Room Heat temperature.
When using only a floor temperature sensor, the thermostat operates the heating
system to maintain the Set Floor Heat temperature. In this case, the thermostat
does not try to control the air temperature. This is ideal for bathrooms and some
kitchen applications where the customer wants their feet to feel warm on the floor.
This is also ideal for garages so that the heating system is not affected by the
opening of the garage door in cold outdoor weather.
When using both a room temperature sensor and a floor temperature sensor, the
thermostat always maintains the Floor Minimum temperature, even when the air
temperature is satisfied. When the air temperature is below the Set Room Heat
temperature, the thermostat operates the heating system to maintain the Set Room
Heat temperature. The floor is never heated above the Floor Maximum setting in
order to protect the floor covering.
The H1 symbol is shown on the display when the thermostat is heating. The heat
can cycle on and off within +/- 1.5°F (1°C) of the Set Room Heat temperature.
Freeze Protection
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The thermostat operates the heat whenever the room or floor temperature falls
below 40°F (4.5°C).
Exercising
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When connected to a tekmarNet®reset control, the thermostat exercises the heat
relay for 10 seconds every 3 days. Exercising helps prevent zone valves or zone
pumps from failing due to precipitate buildup. During exercising, the thermostat
shows “TEST” on the display.
Flushing
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The flushing feature is for open-loop systems that use a domestic hot water tank
as a heat source. Flushing ensures that fresh potable water is circulated through
the system once each day. If the thermostat is connected to a tekmarNet®reset
control with the Flushing feature turned on, the thermostat display will display the
“FLUSH” icon for the duration of the flushing operation.
Hydronic System Supply Pump
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When connected to a tekmarNet
®
system control, the thermostat’s Heat Supply
Pump setting affects how the primary pump or mix pump on the system control
operates. When connected to the boiler bus, the boiler system or primary pump is
operated. When connected to the mix bus, the mix system pump is operated.
If the thermostat operates a motorized or thermal motor zone valve, the Heat Supply
Pump setting should be set to On.

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If the thermostat operates a thermal motor (wax actuator) zone valve, set the Heat
Supply Pump Delay setting to On. This provides a three minute delay to allow the
zone valve to open before the primary or mix pump is turned on.
In special applications with multiple zoning manifolds, the Heat Supply Pump setting
can be set to Off. This allows a Zone Group Pump located on the Zone Manager,
or Wiring Center to operate the pump for the manifold.
DHW Tank Priority
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When a tekmarNet®reset control is heating an indirect Domestic Hot Water (DHW)
tank, the thermostat may shut off the heating zones to allow the DHW tank to recover
quickly. This is determined by the DHW priority of the tekmarNet®reset control.
Warm Weather Shut Down
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When the outdoor air temperature exceeds the Warm Weather Shut Down (WWSD)
setting on the tekmarNet®reset control, the heating system is shut off.
Air Group Operation Section B
In order to prevent heating and cooling at the same time, this thermostat can operate
together with other thermostats on a tekmarNet®system to form an air group.
In an air group, one thermostat is assigned as the air group master. The air group
master operates the cooling equipment for the group. This thermostat can be set
to be a member of the air group.
When operating as an air group, the air temperature readings of all the air group
member thermostats are communicated to the air group master and a temperature
average is determined.
When the air group master is in cooling
operation, the air group member thermostats
do not operate the heating system for air
heating.
If the Set Room Heat temperature is adjusted
while the air group is cooling, the snowflake
icon is flashed to alert the user that the cooling
is presently on. Once the cooling shuts off,
the heating can start operation.
Air Group
Master MemberMember
tekmarNet Communication
Floor Cooling Section C
The thermostat has the option to support radiant floor cooling when connected to a
heat pump control using tekmarNet®communication. The floor cooling setting must
be set to On and the heating system must be in Warm Weather Shut Down (WWSD).
When the heat pump system control operates in cooling mode, all thermostats set for
floor cooling on the tekmarNet®bus all activate the first stage heating contact (H1)
at the same time to allow chilled water into the system. The thermostat continues
to operate the cooling until either the room temperature reaches the Set Heat
temperature plus 3°F (Set Heat+1.5°C) or reaches a minimum temperature of 74°F.
If only a floor sensor is installed, the floor cooling setpoint is 67°F (19.5°C).

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Schedules Section D
Lowering the room temperature setting reduces the amount of fuel required to heat
the building resulting in energy savings.
This thermostat can follow a programmable schedule in order to automatically lower
the room temperature setting. A schedule master such as a Timer 033 is required
in order to gain programmable schedule functionality.
When operating on a programmable schedule, a symbol is shown, as well as a
or a . The or indicates the current operating temperature.
If a symbol does not appear, there is no schedule available.
Display Action
Occupied temperature. No schedule.
Unoccupied temperature. No schedule.
Programmable schedule at occupied temperature.
Programmable schedule at unoccupied temperature.
Scene Display Room Temperature Setting
1or or
Follows programmable schedule or
operates at the occupied temperature.
2Away Away temperature.
3Unoccupied temperature.
Scenes (System Override) Section E
When a programmable schedule is selected, there is a time delay for the temperature
to change from the temperature to the temperature.
The thermostat uses Optimum Start to predict the heat up and cool off rate of
the room. The optimum start feature allows the room to reach the set room
temperature by the time set in the programmable schedule. This applies for both
heating and cooling.
Scenes provide an easy way to save energy while away on vacation, or override a
pre-set schedule when plans change. tekmarNet®devices such as a User Switch
479 provide scene adjustment.
This thermostat responds to the following scenes:
While in the Away scene, the room temperature cannot be changed using the or
buttons. Change the scene from Away to or to change the temperature.

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Troubleshooting
Error Messages (1 of 4)
Error Message Description
CONTROL ERROR The thermostat was unable to correctly read settings from memory and has reloaded the factory default settings. The thermostat does not operate the heating, cooling, or the fan while this error message is present. Error clears once all adjust menu settings in the Installer access level (unlocked) have been checked. Set thermostat’s switch setting #3 to unlock and unlock the tekmarNet®system control. Then press and hold and buttons together for 2 seconds to enter the adjust menu. Continue until all settings have been reviewed. BUS ERROR The tekmarNet®
4 communication bus has either an open or a short circuit. The result is that there
are no communications. Check for loose wires. Check for short circuits between the tN4 and C wires on the House Control, Wiring Center, or Zone Manager. Check for correct polarity between the C and R wires. Error clears automatically once wiring fault has been corrected. If the thermostat is intentionally removed from the tekmarNet®
4 bus, press the and buttons
together to clear the error message.
DEVICE LIMIT The number of devices on the tekmarNet
®
bus has exceeded 24. Devices include tekmarNet
®
Thermostats and Setpoint Controls. The device count must be lowered to 24 or less. If possible, move devices to other tekmarNet®buses. Error clears automatically once the number of devices on the tekmarNet®bus is at 24 or lower.

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Error Messages (2 of 4)
Error Message Description
ADDRESS ERROR This thermostat and another device have been manually given the same tekmarNet®address. Error clears automatically once this thermostat is given a new manually set address or if the thermostat is set to automatic addressing. ROOM SENSOR SHORT CIRCUIT The built-in air temperature sensor has a short circuit fault. Do not confuse this error with the auxiliary room sensor short circuit error. This error cannot be field repaired. Contact your wholesaler or tekmar sales representative for details on repair procedures. ROOM SENSOR OPEN CIRCUIT The built-in air temperature sensor has an open circuit fault. Do not confuse this error with the auxiliary room sensor short circuit error. This error cannot be field repaired. Contact your wholesaler or tekmar sales representative for details on repair procedures. AIR GROUP MEMBER ERROR The thermostat has been selected to join an air group as a member, yet there is no air group master thermostat. Error clears once the thermostat detects an air group master or the air group is set to OFF.

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Error Message Description
FLOOR SENSOR SHORT CIRCUIT The auxiliary floor sensor has a short circuit. Check for damaged wires. Locate and repair the problem as described in the Data Brochure D072 or D 079. Error clears once the floor sensor fault is corrected. FLOOR SENSOR OPEN CIRCUIT The auxiliary floor sensor has an open circuit. Check for loose or damaged wires. Locate and repair the problem as described in the Data Brochure D072 or D079. Error clears once the floor sensor fault is corrected. If the floor sensor was intentionally removed, locate the Room Sensor setting in the Adjust menu and set to On. Power the thermostat down and up to clear the error. OUTDOOR SENSOR SHORT CIRCUIT The auxiliary outdoor sensor has a short circuit. Check for damaged wires. Locate and repair the problem as described in the Data Brochure D070. Error clears after the outdoor sensor fault is corrected. OUTDOOR SENSOR OPEN CIRCUIT The auxiliary outdoor sensor has an open circuit. Check for loose or damaged wires. Locate and repair the problem as described in the Data Brochure D 070. Error clears once the outdoor sensor fault is corrected. If the outdoor sensor was intentionally removed, power the thermostat down and up to clear the error.
Error Messages (3 of 4)