Tekmar 521 User manual

Programmable Thermostat 521
Installation & Operation Manual
521
_
D
12/20
Zoning Replaces: 01/14
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The Programmable Thermostat 521 is
designed for three different modes of
operation: single stage heating, two stages
of heating with a fan, or one stage of
heating and one stage of cooling with
a fan. Two auxiliary sensors may be
added to measure the floor, outdoor or
room temperature. A Slab Sensor 079 is
included to measure floor temperature to
protect the floor from overheating and
enhance comfort. The programmable
schedule supports either a 7 day or 24
hour schedule with 2 or 4 events per day.
A permanent temperature hold button
overrides the programmable schedule.
An optional Adaptor Plate 012 is available
to allow the thermostat to mount onto a
single gang electrical box.
Introduction
Energy Saving Features
• 7 Day Programmable Schedule
Additional Features
• Optimum Start
• Permanent Temperature Hold
• Radiant Floor Heating
• Two Stage Heating
• Cooling
• Fan
• Backlight
• Outdoor and Floor Temperature
Display
• Time Clock
• Four Hour Battery-free Clock
Backup

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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
Table of Contents
Getting Started ...............................2
Important Safety Information ...............3
Installation ...........................................4
Preparation .....................................4
Removing The Thermostat Base ....4
Mounting The Thermostat ...............5
Slab Sensor 079 Installation ...........6
Slab Sensor 079 Wiring .................7
Slab Sensor 079 Testing .................8
Temperature vs. Resistance Table ... 8
Thermostat Wiring .....................9 -11
Testing the Thermostat Wiring ......12
Switch Settings ..................................13
User Interface ....................................14
Home Screen ................................14
Symbols Description .....................14
Programmable Settings .....................15
Fan Menu ......................................15
Set Temp Menu .............................16
Time Menu ....................................17
Schedule Menu ........................18-19
Setup Menu ............................. 20-21
Sequence of Operation ......................22
Mode Button Operation ................22
Heating Operation .........................22
Cooling Operation .........................23
Fan Operation ...............................23
Time Clock ....................................24
Programmable Schedule ..............24
Optimum Start ...............................25
Temperature Adjustment...............25
Access Levels ...............................25
Troubleshooting .................................26
Error Messages ............................26
Frequently Asked Questions .........27
Technical Data ..............................27
Limited Warranty and Product
Return Procedure .........................28

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To avoid serious personal injury and damage to the equipment:
Important Safety Information
It is your responsibility to ensure that this control is safely installed
according to all applicable codes and standards. tekmar is not responsible
for damages resulting from improper installation and/or maintenance.
• Read Manual and all product labels BEFORE using the equipment.
Do not use unless you know the safe and proper operation of this
equipment.
• Keep this Manual available for easy access by all users.
• Replacement Manuals are available at tekmarControls.com
• Disconnect all power before opening the control.
• It is the installers responsibility to ensure that this control is safely installed according
to all applicable codes and standards.
• Improper installation and operation of this control could result in damage to the
equipment and possibly even personal injury or death.
• 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.
• Do not attempt to service the control. There are no user serviceable parts inside
the control. Attempting to do so voids warranty.

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Preparation
Installation
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 less than 90%. 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 5 conductor, 18 AWG wire.
Installation Location ------------------------------------------------ ------------------------------------------------
• tekmar or jeweller screwdriver
• Phillips head screwdriver
• Wire Stripper
Tools Required ----------------------------------------------------- -----------------------------------------------------
Materials Required ------------------------------------------------- -------------------------------------------------
• 18 AWG LVT Solid Wire
(Low Voltage Connections)
Removing The Thermostat Base
To remove the thermostat base:
• Locate the tab on the bottom of the thermostat.
• Push the tab with either your thumb or with a
screwdriver.
• Lift the thermostat front away from the
thermostat’s base.

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Mounting The Thermostat
If mounting directly to the wall:
• Drill holes and install the wall anchors.
• Feed the wiring through the large hole in the thermostat base.
• Fasten the thermostat base to the wall using the wood screws to the wall
anchors.
• Terminate wiring to the wiring strip.
• Push the thermostat front onto the thermostat base.
If a single gang box is used:
• Adapter Plate 012 is required (sold separately).
• Feed the wiring through the hole in the adaptor plate and the thermostat base.
• Fasten the adaptor plate to the gang box.
• Fasten the base of the thermostat to the adaptor plate.
• Terminate wiring to the wiring strip.
• Push the thermostat front onto the thermostat base.
Wall
Thermostat
Front
Thermostat
Base
3 1/4"
(83 mm)
Stud
Gang
Box
Thermostat
Front
Thermostat
Base
Adapter Plate 012

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Thick Floor Coverings (greater than 3/8" (10 mm))
If a thick floor covering is to be installed directly to the subfloor, a groove 1/8" (4 mm) wide
by 1/16" (2 mm) deep can be cut into the back of the flooring material to accommodate
the wire for the sensor. Ensure that the sensor is located in such a position that the
attached wire is able to reach to a suitable junction location.
Splices under the floor covering should be avoided
to ensure trouble free operation. A groove 3/16"
(5 mm) wide by 3/16" (5 mm) deep by 1-3/4" (45
mm) long should be cut to accommodate the
sensor. The sensor should be located mid way
between the heating elements to ensure a proper
temperature reading.
If it is not practical to cut a groove in the surface
covering, follow the installation method used for
thin floor coverings.
Slab Sensor 079 Installation
Thin-Set or Thin-Pour Applications
If the floor covering is to be installed over either a thin-set or thin-pour material of sufficient
depth, the 079 slab sensor can be placed directly into either the thin-set material or the
thin-pour material and covered over. Ensure
that the sensor is located in such a position that
the attached wire is able to reach to a suitable
junction location. Splices within the thin-set or
thin-pour should be avoided to ensure trouble
free operation. The sensor should be located
mid way between the heating elements to ensure
a proper temperature reading.
Tiles
Thin-set
Electric
Cables
Thin Floor Coverings (less than 3/8" (10 mm))
If a thin floor covering is to be installed directly to the subfloor, a groove 1/8" (4 mm)
wide by 1/16" (2 mm) deep can be cut into the surface of the subfloor to accommodate
the wire for the sensor. Ensure that the sensor is located in such a position that the
attached wire is able to reach to a suitable junction
location. Splices under the floor covering should
be avoided to ensure trouble free operation.
A groove 3/16" (5 mm) wide by 3/16" (5 mm)
deep by 1-3/4" (45 mm) long should be cut to
accommodate the sensor. The sensor should be
located mid way between the heating elements to
ensure a proper temperature reading.
Hardwood
Subfloor
Hardwood
Subfloor
New Installations --------------------------------------------------- ---------------------------------------------------

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Tile Floor Coverings
If a Slab Sensor 079 is to be installed into an existing tile floor with sufficiently large
grout lines, the sensor and wire can be installed in one of the grout lines between the
tiles. Select a low traffic area of the floor that is mid way between the heating elements
for the sensor location. Ensure that the sensor is located in such a position that the
attached wire is able to reach to a suitable junction location. Splices within the grout
should be avoided to ensure trouble free operation. Remove the appropriate grout line
and place the sensor and wire in the floor. Re-grout the area.
Installing the Sensor to the Bottom of a Subfloor
If the sensor is to be installed to the bottom of a subfloor, cut a piece of 1" (25 mm)
thick rigid insulation into a 6" (150 mm) by 6" (150 mm) square. A groove 3/16" (5 mm)
wide by 3/16" (5 mm) deep by 1-3/4" (45 mm) long should be cut into the insulation to
accommodate the sensor. Place the sensor in the groove and sandwich the sensor
between the insulation and the subfloor. Use a suitable fastening method to affix the
insulation to the subfloor.
Retrofit Installations ------------------------------------------------ ------------------------------------------------
The Slab Sensor 079 is supplied with 10' (3 m) of cable. If a longer length is
required, 24 AWG or larger wire can be spliced onto the two wires from the sensor.
The splices should be properly soldered and protected in an accessible junction
box. Follow the sensor testing instructions given in this brochure and then connect
the wires to the control.
Slab Sensor 079 Wiring
Do not run sensor wires parallel to telephone or power cables. If the sensor
wires are located in an area with strong sources of electromagnetic interference,
shielded cable or twisted pair should be used or the wires can be run in a grounded
metal conduit.

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Slab Sensor 079 Testing
A good quality test meter capable of measuring up to 5,000 kΩ (1 kΩ = 1000Ω) is
required to measure the sensor resistance. In addition to this, the actual temperature
must be measured with either a good quality digital thermometer, or if a thermometer
is not available, a second sensor can be placed alongside the one to be tested and
the readings compared.
First measure the room temperature using the thermometer. Disconnect the S1 or S2
and Com wires from the thermostat. Using an electrical meter, measure the resistance
of the S1 or S2 and Com wires at the thermostat location. Using the temperature
versus resistance table, estimate the temperature measured by the sensor. The sensor
measurement and thermometer readings should be close. If the test meter reads a very
high resistance, there may be a broken wire, a poor wiring connection or a defective
sensor. If the resistance is very low, the wiring may be shorted, there may be moisture
in the sensor or the sensor may be defective. To test for a defective sensor, measure
the resistance directly at the sensor location. Once the test has been completed,
reconnect the S1 or S2 and Com wires to the thermostat.
Do not apply voltage to the temperature sensor terminals at any time as damage to
the sensor may result.
Temperature vs. Resistance Table
Temperature Resistance
°F °C
-50 -46 490,813
-45 -43 405,710
-40 -40 336,606
-35 -37 280,279
-30 -34 234,196
-25 -32 196,358
-20 -29 165,180
-15 -26 139,402
-10 -23 118,018
-5 -21 100,221
0-18 85,362
5-15 72,918
10 -12 62,465
15 -9 53,658
20 -7 46,218
Temperature Resistance
°F °C
25 -4 39,913
30 -1 34,558
35 2 29,996
40 4 26,099
45 7 22,763
50 10 19,900
55 13 17,436
60 16 15,311
65 18 13,474
70 21 11,883
75 24 10,501
80 27 9,299
85 29 8,250
90 32 7,334
95 35 6,532

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Temperature vs. Resistance Table - Continued
Temperature Resistance
°F °C
100 38 5,828
105 41 5,210
110 43 4,665
115 46 4,184
120 49 3,760
125 52 3,383
130 54 3,050
135 57 2,754
140 60 2,490
145 63 2,255
150 66 2,045
155 68 1,857
160 71 1,689
Temperature Resistance
°F °C
165 74 1,538
170 77 1,403
175 79 1,281
180 82 1,172
185 85 1,073
190 88 983
195 91 903
200 93 829
205 96 763
210 99 703
215 102 648
220 104 598
225 107 553
Thermostat Wiring
Zone Valve --------------------------------------------------------- ---------------------------------------------------------
C
N
L
R
CR Y/W2 Rc GGRh W1 S1 S2Com
No Power
TT
Zone
Valve
Boiler
Transformer
Field Jumper Required:
R to Rh

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Wiring Center 315 or 316 -------------------------------------------- --------------------------------------------
Relay 003 ---------------------------------------------------------- ----------------------------------------------------------
Switching Relay ---------------------------------------------------- ----------------------------------------------------
T T
C
N
L
R
CR Y/W2 Rc GGRh W1 S1 S2Com
No Power
2
1
8
7
3
4
5
6
Thermostat Wiring
Boiler
Relay
003
Pump
Transformer
tN4 CW
R
CR Y/W2 Rc GGRh W1 S1 S2Com
No Power
Wiring Center
CR Y/W2 Rc GGRh W1 S1 S2Com
No Power
RW
24 V
RW
HNXX HNHN NH
Com Switching Relay
Zone 1 Zone 2 Zone 3
Class 2
Transformer
RW
Zone 1 Zone 2 Zone 3
Pump
N L
Field Jumper Required:
R to Rh
Field Jumper Required:
R to Rh

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Thermostat Wiring
Air Conditioner ----------------------------------------------------- -----------------------------------------------------
Furnace (second stage heat) ----------------------------------------- -----------------------------------------
Furnace and Air Conditioner ---------------------------------------- ----------------------------------------
RYG
CR Y/W2 Rc GGRh W1 S1 S2Com
No Power
Air
Conditioner
CR Y/W2 Rc GGRh W1 S1 S2Com
No Power
R W G
Furnace
CR Y/W2 Rc GGRh W1 S1 S2Com
No Power
C
R
W
Y
G
Furnace
Air
Conditioner
Field Jumper Required:
• R to Rh
• Rh to Rc
• Rc to G
Field Jumper Required:
Rc to G
Field Jumper Required:
Rc to G

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Testing the Thermostat Wiring
Testing the Power -------------------------------------------------- --------------------------------------------------
If the thermostat display turns on, this indicates that power is applied correctly. In the
event that the display is permanently off:
1. Remove the thermostat front.
2. Use an electrical meter to measure voltage between the R and C wiring terminals.
For AC power supplies the voltage should measure between 10 to 30 V (ac). For
DC power supplies the voltage should measure between 10 to 30 V (dc).
3. If the voltage on the R and C wire terminations is continuous and the thermostat
display is not on, the thermostat may have a fault. Contact your tekmar sales
representative for assistance.
If the thermostat display initially powers on but later shuts off intermittently, there may
be a short circuit from the W1, W2, Y or G wire to the power common or ground, or
the power supply is too small to power the load.
Testing the First Stage Heat Output Wiring --------------------------- ---------------------------
1. Press the Mode button and set to Heat.
2. Press the button and set the heating temperature above the current room
temperature. Make sure the display does not flash “Max” if using a floor sensor.
3. When the “Heat On” symbol appears on the display, use an electrical meter to check
for voltage on the W1 and C wires connected to the zone valve, wiring center, relay
or switching relay. The electrical meter should read 10 to 30 V (ac) or (dc).
4. If the W1 and C wires have voltage, check the zone valve, wiring center, relay or
pump to determine if the heat device is operating correctly.
Sensors ------------------------------------------------------------ ------------------------------------------------------------
CR Y/W2 Rc GGRh W1 S1 S2Com
No Power
Indoor
Sensor
076, 077, 084
Outdoor
Sensor
070
Slab
Sensor
079
Indoor
Sensor
076, 077, 084
Slab
Sensor
079
Or
Or Or

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Switch Position Action
1
ON
LOCK ACCESS LEVEL
Thermostat is locked and the access level cannot be changed. Set
to Lock when installation has been completed.
OFF
UNLOCK ACCESS LEVEL
Thermostat is unlocked and the access level may be changed. Go
to the Setup menu to change the access level. Set to Unlock during
the installation process.
2
ON
H/C/F
Thermostat is configured to operate one stage heating, one stage
cooling and fan.
OFF
1H OR 2H
Thermostat is configured to operate one or two stage heating with
a fan.
Switch Settings
Testing the Cooling Output Wiring ----------------------------------- -----------------------------------
Cooling is only available when the switch setting is set to H/C/F.
1. Press the Mode button and set to Cool.
2. Press the button and set the cooling temperature below the current room
temperature setting.
3. When the “Cool On” symbol appears on the display, use an electrical meter to check
for voltage on the Y and C wires on the cooling equipment. The meter should read
10 to 30 V (ac) or (dc).
Testing the Fan Output Wiring --------------------------------------- ---------------------------------------
The fan is only available when the Fan Mode setting is not set to off.
1. Press both the and buttons together.
2. The display will show FAN MENU. Press the PRGM button.
3. Press the up button to set the fan to On.
4. When the fan symbol appears on the display, use an electrical meter to check for
voltage on the G and C wires on the fan equipment. The meter should read 10 to
30 V (ac) or (dc).

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HEAT ON
Heat is turned on.
COOL ON
Cooling is turned on.
FAN
The fan is turned on.
MODE HEAT
The heating system is
allowed to operate.
MODE COOL
The cooling system is
allowed to operate.
MODE OFF
The heating and cooling
systems are off.
SUN
Schedule operating at the
occupied temperature.
MOON
Schedule operating at the
unoccupied temperature.
WARNING SYMBOL
Indicates an error is present.
HOLD
Permanently holds the
temperature and overrides
the schedule.
MIN
The floor is at or below the
floor minimum temperature.
MAX
The floor has reached the
floor maximum temperature.
Home Screen
Symbols Description
User Interface
Sa
Floo
r
F
F
MIN
Heat On Cool On
Room Floor
Heat Cool
Off
MAX
MODE
FrThWeTuMoSu
P
Mode Button
Change operation
from Heat, Cool
and Off.
Hold Button
Permanently
overrides the
schedule. Press
hold to cancel.

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Programmable Settings
1. Press and hold down both the and buttons together to enter the Programming
Menus.
2. While in the
Programming
Menus, the MODE
button changes
function to become
the MENU button.
Press the MENU
button to change
from one menu to
the next.
PRGM
MENU
PRGM
MENU
PRGM
MENU
PRGM
MENU
PRGM
MENU
Navigation
PRGM
MENU
3. While in the
Programming Menus,
the HOLD button
changes function to
become the PRGM
(program) button.
Press the PRGM
button to enter the
menu.
4. While inside a menu, the HOLD button changes to become the ITEM button.
Press the ITEM button to change from one setting to the next.
5. Press the or button to change and save the setting's value.

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Setting Display
SET HEAT ROOM
Set the room heating temperature for the event.
Access Level: Installer, User Range: 40 to 95°F (4.5 to 35.0°C)
Conditions: Room Sensor On or Sensor 1 or 2 is
set to Room. Default: 70°F (21.0°C)
SET HEAT ROOM
Set the room heating temperature for the event.
Access Level: Installer, User Range: 40 to 95°F (4.5 to 35.0°C)
Conditions: Room Sensor On or Sensor 1 or 2 is
set to Room and Schedule is set to On. Default: 65°F (18.5°C)
SET COOL ROOM
Set the room cooling temperature for the event.
Access Level: Installer, User Range: 50 to 100°F (10.0 to 38.0°C)
Conditions: Room Sensor On or Sensor 1 or 2 is
set to Room. Default: 78°F (25.5°C)
SET COOL ROOM
Set the room cooling temperature for the event.
Access Level: Installer, User Range: 50 to 100°F (10.0 to 38.0°C)
Conditions: Room Sensor On or Sensor 1 or 2 is
set to Room and Schedule is set to On. Default: 85°F (29.5°C)
SET FLOOR
Set the floor heating temperature for the event.
Access Level: Installer, User Range: OFF, 40 to 122°F
(OFF, 4.5 to 50.0°C)
Conditions: Sensor 1 or 2 is set to Floor. Default: 72°F (22.0°C)
Set Temp Menu
Fan Menu
Setting Display
FAN
Select if the fan should operate continuously (On)
or only together with the heating or cooling equip-
ment (Auto).
Access Level: Installer, User Range: Auto or On
Conditions: Only available when FAN MODE is
not set to OFF and a room temperature sensor is
available.
Default: Auto

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Time Menu
Setting Display
MINUTES
Set the current time minutes.
Access Level: Installer, User Range: 00 to 59
Conditions: Always available. Default: 00
HOURS
Set the current time hours.
Access Level: Installer, User Range: 12 AM to 11 PM or 00 to 23
Conditions: Always available. Default: 12 AM
DAY OF WEEK
Select the current day of the week.
Access Level: Installer, User Range: Sunday to Saturday
Conditions: Always available. Default: Sunday
TIME MODE
Select either 12 or 24 hour time format.
Access Level: Installer, User Range: 12 or 24 hour
Conditions: Always available. Default: 12 hour
CLOCK
Select whether to show the time clock on the display.
Access Level: Installer, User Range: OFF or ON
Conditions: The time is always shown when a sched-
ule is used and the clock setting option is hidden.
Default: OFF
Setting Display
SET FLOOR
Set the floor heating temperature for the event.
Access Level: Installer, User Range: OFF, 40 to 122°F
(OFF, 4.5 to 50.0°C)
Conditions: Sensor 1 or 2 is set to Floor and
Schedule is set to On.
Defaults
Air & floor sensors: 65°F (18.5°C)
Floor sensor only: OFF
SET FLOOR MAXIMUM
Set the maximum floor heating temperature.
MAX
Access Level: Installer Range: 40 to 122°F, OFF
(4.5 to 50.0°C, OFF)
Conditions: Sensor 1 or 2 is set to Floor. Default: 85°F (29.5°C)
Set Temp Menu

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Schedule Menu (1 of 2)
The schedule menu can operate on a 24 hour or 7 day repeating schedule. When a
24 hour schedule is selected, “SuMoTuWeThFrSa” is shown on the top of the screen
to show that the event time applies to all days of the week. When a 7 day schedule
is selected, each individual day of the week is shown with the event time.
Setting Display
EVENT 1
The first programmable schedule time period of
the day. The temperature settings are used
during this time period.
SaFrThWeTuMoSu
Access Level: Installer, User Range: 12:00 AM to 11:50 PM, SKIP
or 00:00 to 23:50, SKIP
Conditions: Schedule setting is set to On. Default: 6:00 AM
EVENT 2
The second programmable schedule time period
of the day. The temperature settings are used
during this time period.
SaFrThWeTuMoSu
Access Level: Installer, User Range: 12:00 AM to 11:50 PM, SKIP
or 00:00 to 23:50, SKIP
Conditions: Schedule setting is set to On.
Default:
10:00 PM when Event/Day is 2
8:00 AM when Event/Day is 4
EVENT 3
The third programmable schedule time period
of the day. The temperature settings are used
during this time period.
SaFrThWeTuMoSu
Access Level: Installer, User Range: 12:00 AM to 11:50 PM, SKIP
or 00:00 to 23:50, SKIP
Conditions: Schedule setting is set to On. Default: 6:00 PM
EVENT 4
The fourth programmable schedule time period
of the day. The temperature settings are used
during this time period.
SaFrThWeTuMoSu
Access Level: Installer, User Range: 12:00 AM to 11:50 PM, SKIP
or 00:00 to 23:50, SKIP
Conditions: Schedule setting is set to On. Default: 10:00 PM

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Setting Display
SCHEDULE
Select if the thermostat should change the temperature
automatically using a programmable schedule.
Access Level: Installer, User Range: OFF or On
Conditions: Always available Default: OFF
EVENT PER DAY
Select either two or four scheduled events per day.
Access Level: Installer, User Range: 2 or 4
Conditions: Schedule setting is set to On. Default: 2
24 HOUR / 7 DAY
Select either a 24 hour or a 7 day repeatable
schedule.
Access Level: Installer, User Range: 24 hour or 7 day
Conditions: Schedule setting is set to On. Default: 24 hour
OPTIMUM START
Select whether or not to use optimum start. The
thermostat learns the heat up rate of the room and
starts heating in advance of Event 1 or Event 3.
Only applies to radiant floor heating, baseboard or
radiator heating.
Access Level: Installer, User Range: OFF or ON
Conditions: Schedule setting is set to On. Default: ON
Schedule Menu (2 of 2)

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Setup Menu (1 of 2)
Setting Display
ACCESS
Selects the access level of the thermostat, which
determines which menus and items are available.
Access Level: Installer, User Range: Installer or User
Conditions: Only available when switch setting 1 is
set to Unlocked. Default: Installer
UNITS
Select the temperature units.
Access Level: Installer, User Range: °F or °C
Conditions: Always available. Default: °F
LIGHT
Select when the display back light should operate.
Auto operates the back light for 30 seconds after a
keystroke.
Access Level: Installer, User Range: OFF, AUTO, ON
Conditions: Always available. Default: AUTO
TYPE
Device Type number. Hold the button to view
the software version.
Access Level: Installer, User Range: 521
Conditions: Always available. Default: 521
SENSOR 1
Select the type of auxiliary sensor 1.
Access Level: Installer Range: NONE, ROOM, FLOR
(floor), OUT (Outdoor)
Conditions: Available when a sensor is automatically
detected on auxiliary sensor 1 input. Default: FLOR
SENSOR 2
Select the type of auxiliary sensor 2.
Access Level: Installer Range: NONE, ROOM, FLOR
(floor)
Conditions: Available when a sensor is automatically
detected on auxiliary sensor 2 input. Default: ROOM
ROOM SENSOR
Select if the built-in room temperature sensor is on
or off.
Room
Access Level: Installer Range: OFF or ON
Conditions: When switch setting 2 is set to 1H or 2H,
an auxiliary sensor must be set to Room or Floor.
When switch setting 2 is set to H/C/F, an auxiliary
sensor must be set to Room.
Default: ON