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521_D
Programmable Thermostat 521
Installation & Operation Manual
Introduction
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.
01/14
Zoning
Replaces: New
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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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
Getting Started
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.
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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.
To avoid serious personal injury and damage to the equipment:
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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Installation
------------------------------------------------
-----------------------------------------------------
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Preparation
Tools Required
•
tekmar or jeweller screwdriver
Phillips head screwdriver
•
Materials Required
18 AWG LVT Solid Wire
•
(Low Voltage Connections)
Installation Location
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.
-----------------------------------------------------
Wire Stripper•
-------------------------------------------------
------------------------------------------------
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
Stud
3 1/4"
(83 mm)
Gang
Box
Thermostat
Front
Adapter Plate 012
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.
•
Thermostat
Thermostat
Front
Base
Wall
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.
•
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Slab Sensor 079 Installation
---------------------------------------------------
New Installations
---------------------------------------------------
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
Thin-set
Electric
Cables
Tiles
free operation. The sensor should be located
mid way between the heating elements to ensure
a proper temperature reading.
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)
Hardwood
Subfloor
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.
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"
Hardwood
(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
Subfloor
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.
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Retrofit 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.
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.
Slab Sensor 079 Wiring
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.
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Slab Sensor 079 Testing
A good quality test meter capable of measuring up to 5,000 k (1 k = 1000) 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
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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 4 6 4 ,18 4
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
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TT
Zone
Valve
Boiler
R
C
L
N
Transf orme r
Field Jumper Required:
R to Rh
C R
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Y/W2
Rc GGRh W1 S1 S2Com
No Power
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--------------------------------------------
----------------------------------------------------------
----------------------------------------------------
Thermostat Wiring
Relay 003
----------------------------------------------------------
3
T T
4
5
6
Relay
003
Boiler
Pump
L
N
Wiring Center 315 or 316
tN4 C W
Wiring Center
2
1
8
7
R
C
R to Rh
C R
Y/W2
Rc GGRh W1 S1 S2Com
No Power
Trans for mer
--------------------------------------------
Field Jumper Required:
R to Rh
Field Jumper Required:
C R
R
Y/W2
Rc GGRh W1 S1 S2Com
No Power
Switching Relay
24 V
Com
Class 2
Transformer
----------------------------------------------------
RW
RW
RW
Zone 1 Zone 2 Zone 3
Switching Relay
Zone 1 Zone 2 Zone 3
HNXX HNHN NH
Pump
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NL
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C R
Rc GGRh W1 S1 S2Com
No Power
Y/W2
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Thermostat Wiring
-----------------------------------------------------
-----------------------------------------
----------------------------------------
Air Conditioner
-----------------------------------------------------
Furnace (second stage heat)
Field Jumper Required:
Rc to G
R
Y
G
C R
Y/W2
Rc GGRh W1 S1 S2Com
No Power
Air
Conditioner
-----------------------------------------
Field Jumper Required:
Rc to G
R W G
C R
Y/W2
Rc GGRh W1 S1 S2Com
No Power
Furnace and Air Conditioner
Field Jumper Required:
R to Rh
•
Rh to Rc
•
Rc to G
•
G
Y
W
R
C
Air
Conditioner
Furnace
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Furnace
----------------------------------------
C R
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Y/W2
Rc GGRh W1 S1 S2Com
No Power
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--------------------------------------------------
---------------------------
Sensors
------------------------------------------------------------
------------------------------------------------------------
Indoor
Sensor
076, 077, 084
Slab
Sensor
079
Outdoor
Sensor
070
Or Or
C R
Y/W2
Rc GGRh W1 S1 S2Com
No Power
Or
Indoor
Sensor
076, 077, 084
Slab
Sensor
079
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.
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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
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).
and buttons together.
---------------------------------------
Switch Settings
Switch
1
Position
ON
OFF
Action
LOCK ACCESS LEVEL
Thermostat is locked and the access level cannot be changed. Set
to Lock when installation has been completed.
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.
H/C/F
ON
2
OFF
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Thermostat is configured to operate one stage heating, one stage
cooling and fan.
1H OR 2H
Thermostat is configured to operate one or two stage heating with
a fan.
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User Interface
Home Screen
MIN
MAX
Sa
FrThWeTuMoSu
P
F
F
Floor
MODE
Heat Cool
Mode Button
Change operation
from Heat, Cool
and Off.
Symbols Description
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.
Off
Room Floor
Heat On
Cool On
Hold Button
Permanently
overrides the
schedule. Press
hold to cancel.
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.
MODE COOL
The cooling system is
allowed to operate.
MODE OFF
The heating and cooling
systems are off.
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MIN
The floor is at or below the
floor minimum temperature.
MAX
The floor has reached the
floor maximum temperature.
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Programmable Settings
Navigation
1. Press and hold down both the
Menus.
2. While in the
Programming
Menus, the MODE
button changes
function to become
MENU
the MENU button.
Press the MENU
button to change
from one menu to
the next.
MENU
and buttons together to enter the Programming
3. While in the
Programming Menus,
the HOLD button
PRGM
changes function to
become the PRGM
(program) button.
Press the PRGM
button to enter the
menu.
PRGM
MENU
MENU
PRGM
PRGM
MENU
MENU
PRGM
PRGM
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
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or button to change and save the setting's value.
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Fan Menu
Setting Display
FAN
Select if the fan should operate continuously (On)
or only together with the heating or cooling equipment (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
Default: Auto
available.
Set Temp Menu
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.
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: 70°F (21.0°C)
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)
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Set Temp Menu
Setting Display
SET FLOOR
Set the floor heating temperature for the event.
Access Level: Installer, User
Conditions: Sensor 1 or 2 is set to Floor and
Schedule is set to On.
SET FLOOR MAXIMUM
Set the maximum floor heating temperature.
Range: OFF, 40 to 122°F
(OFF, 4.5 to 50.0°C)
Defaults
Air & floor sensors: 65°F (18.5°C)
Floor sensor only: OFF
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)
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 schedule is used and the clock setting option is hidden.
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Default: OFF
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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.
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.
Access Level: Installer, User
Range: 12:00 AM to 11:50 PM, SKIP
or 00:00 to 23:50, SKIP
Default:
Conditions: Schedule setting is set to On.
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.
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.
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
SaFrThWeTuMoSu
SaFrThWeTuMoSu
SaFrThWeTuMoSu
SaFrThWeTuMoSu
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Schedule Menu (2 of 2)
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
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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.
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.
Default: Installer
Access Level: Installer
Conditions: Available when a sensor is automatically
detected on auxiliary sensor 1 input.
Range: NONE, ROOM, FLOR
(floor), OUT (Outdoor)
Default: FLOR
SENSOR 2
Select the type of auxiliary sensor 2.
Access Level: Installer
Conditions: Available when a sensor is automatically
detected on auxiliary sensor 2 input.
Range: NONE, ROOM, FLOR
(floor)
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
Default: ON
sensor must be set to Room.
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Setup Menu (2 of 2)
Setting Display
W2 RELAY
Select if a second stage heat is available.
Access Level: Installer Range: OFF or On
Conditions: Available when switch setting 2 is set
to 1H or 2H.
Default: OFF
W2 DELAY
Select the time delay that the second stage must
wait before turning on.
Access Level: Installer Range: 1 to 180 minutes
Conditions: Available when switch setting 2 is set to
1H or 2H and W2 Relay is set to On.
Default: 20 minutes
W2 DIFFERENTIAL
Select the differential below the Set Heat setpoint
at which the second stage heat can turn on.
Access Level: Installer, User Range: 1.5 to 8.0°F (1.5 to 8.0°C)
Conditions: Available when switch setting 2 is set to
1H or 2H and W2 Relay is set to On.
Default: 2.0°F
FAN MODE
Select how the fan should operate together with
the W1, W2 and Y relays.
Range:
OFF, Y, W1, W1+Y
Access Level: Installer, User
(Switch setting is H/C/F)
Conditions:
When switch setting 2 is set to H/C/F, always
available.
When switch setting 2 is set to 1H or 2H, available
when a room sensor is available. If a floor sensor is
available then W2 must also be set to On.
Fan mode combinations with W1 are unavailable
when a floor sensor is connected.
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OFF, W1, W2, W1+2
(Switch setting is 1H or 2H)
Default:
Y (Switch setting 2 is H/C/F)
OFF (Switch setting 2 is 1H or 2H)
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Sequence of Operation
----------------------------------------------------------------------------
-------------------------------------------------
---------------------------------------
Mode Button Operation
Pressing the Mode button selects the operation of the thermostat to be either
Heating, Cooling, or Off. The thermostat must be configured for heat/cool/fan
operation in order for the cooling operation to be available.
Heating Operation
Heating is available when the Mode is set to Heat. To change the heat temperature
setting, push the or button to select a preferred temperature setting for the current
schedule time period. The Heat On symbol is shown on the display when the thermostat
is heating.
To change the temperatures for the other time periods, enter the Set Temp menu by
pressing both the and buttons together, press Menu to locate the Set Temp menu,
and press PRGM to enter the menu.
Hydronic Systems
When operating a hydronic radiant floor, baseboard or radiator heating system, the
thermostat uses Pulse Width Modulation (PWM) operation
off within +/- 1.5°F (1°C) of the temperature setting.
Forced Air Systems
When operating a forced air heating system, the thermostat uses a differential of +/-
0.7°F (0.4°C).
Temperature Sensor Location
The thermostat can operate the heating system based upon either an air temperature
sensor, a floor temperature sensor, or a combination of both the air and floor temperature
sensors together.
Air Temperature Only
If there is only an air temperature sensor (no floor sensor), the thermostat maintains
the desired air temperature.
Floor Temperature Only
If the air sensor has been disabled, the thermostat will only maintain floor temperature
and ignore air temperature. This operation is recommended for areas such as bathrooms
to ensure that tile floors are warm to the touch.
Floor and Air Temperature
If the air sensor is turned on and a floor sensor is connected, the thermostat will maintain
the desired air temperature as well as a minimum floor temperature.
This operation is recommended for areas with large windows that allow the sun to shine
into a room and keep it warm without the need for heat. This can allow the floors to
cool off during the afternoon. When the sun goes down, it can take a long time for the
floors to get warm again. This may cause the room to cool off too much in the early
evening. A floor minimum setting can help with this condition by maintaining a floor
minimum temperature. Keep in mind the floor minimum temperature will override the
air temperature, and if set too high, may overheat the room.
----------------------------------------------------------------------------
and cycles the heat on and
-------------------------------------------------
---------------------------------------
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-------------------------------------------------
This operation is also recommended for rooms with hardwood floors. Setting floor
---------------------------------------------------
minimum and maximum temperatures is a way of enhancing the comfort of the living
space while protecting floor coverings.
90°F (32°C)
Feels hot to the touch
80 to 85°F (26 to 30°C)
Feels warm to the touch
70°F (21°C)
Feels cool to the touch
40 to 45°F (5 to 7°C)
Feels cold to the touch
Two -Stage Heating
-------------------------------------------------
The thermostat supports two-stage
heating. The second stage heat turns
on when the air temperature falls
below the Set Heat minus the W2
Differential setting and the W2 Delay
time expires. The second stage heat
turns off when the room temperature
reaches the Set Heat setting.
Suggested maximum for all floor
types other than wood.
Bathrooms and kitchens. Suggested
maximum for wood floors.
Rooms with large windows preventing
under heating in the evening.
Freeze protection for garages.
W1 O
W1
Dierential
Set Heat Room
W2 O
W1 On
W2
Dierential
W2 On
Freeze Protection
---------------------------------------------------
The thermostat operates the heat whenever the room temperature falls below 40°F
(4.5°C) even when the mode is set to off.
Cooling Operation
Cooling is available when the Mode is set to Cool.
for heat/cool/fan operation in order for the cooling operation to available.
To change the cool temperature setting, push the or button to select a preferred
temperature setting for the current schedule time period. The Cool On symbol is shown
on the display when the thermostat is cooling.
To change the temperatures for the other time periods, enter the Set Temp menu by
pressing both the and buttons together, press Menu to locate the Set Temp menu,
and press PRGM to enter the menu.
When operating a forced air cooling system, the thermostat uses a differential of +/-
0.7°F (0.4°C).
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The thermostat must be configured
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Fan Operation
A fan is available when the thermostat operates a forced air heating or cooling system.
The fan can be set to On to allow air circulation through the building. This is useful if the
air in the room is stale or if circulating cool air from a basement throughout a home can
reduce the temperature in the upper floor without operating the cooling equipment.
Time Clock
The thermostat includes a time clock that is automatically visible in the Home
menu when a programmable schedule is used. If the schedule is not used, the
user has the option to select whether the time is shown in the Home menu.
During a loss of power, the thermostat continues to keep the correct time
and date for at least 4 hours. If the power is off for more than 4 hours, the user
will need to set the time.
Programmable Schedule
Energy savings can be achieved by lowering the heating temperature and increasing
the cooling temperature when the building is unoccupied or during the night.
When operating on a programmable schedule, a or a symbol is shown in the
home menu. The or indicates the current operating temperature.
All schedules are stored in permanent memory and are not affected by a loss
of power.
Display Action
Day temperature
Night temperature
This thermostat can operate on a programmable schedule in order to automatically
lower the room temperature setting. The schedule can be off or on.
The thermostat can support schedules that have either:
2 events per day
•
4 events per day
•
Schedules with four events per day are common for residential use while two events
per day are common for commercial installations.
The schedules can be repeated every:
24 hours
•
7 days (week)
•
A 7 day schedule allows a unique time to be set to change the temperature for each
day of the week.
The schedule also includes a “SKIP” option that allows the programmable schedule to
skip a temperature change and remain at the previous temperature setting. The “SKIP”
setting can be found between 11:50 PM (23:50 hours) and 12:00 AM (0:00 hours).
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Optimum Start
-------------------------------
------------------------------
----------------------------------------------------
When a programmable schedule is selected, there is a time delay for the room to warm
up from the temperature to the temperature. The thermostat has the option to use
Optimum Start to predict the heat up rate of the room. When Optimum Start is set to On,
the heating is started in advance to allow the room to reach the Set Room temperature
at the time set in the programmable schedule. The optimum start only applies to radiant
floor heating, baseboard or radiator heating and does not apply when a forced air fan
is used with the heating system.
Temperature Adjustment
Permanent Adjustment - No Schedule
When no programmable schedule is used, push
set the “Set Heat Room” or “Set Cool Room” temperature. This thermostat is capable
of controlling both air and floor temperature.
Permanent Adjustment - With Schedule
When a programmable schedule is used, there are two temperature settings available,
one for the
or buttons
period is changed.
1. To adjust the temperature for both time periods, press and hold
for 3 seconds to enter the programming menus.
2. Enter the “SET TEMP” menu to adjust the following settings:
•
•
•
•
•
•
Permanent Hold
The thermostat includes a Hold button. When the Hold button is pressed, the thermostat
stops operating based on the programmable schedule and the hold temperature can
be set using the
and resume operating based upon the programmable schedule. If both an air and floor
sensor are installed, the floor maintains the Set Floor temperature setting when the
hold temperature is higher than the Set Heat Room
set lower than the Set Heat Room , the floor does not maintain a temperature.
time period and another for the time period. When pushing
to change the temperature, only the temperature for the current time
Set Heat Room
Set Heat Room (air heating)
Set Floor (floor heating)
Set Floor (floor heating)
Set Cool Room (air cooling)
Set Cool Room (air cooling)
(air heating)
----------------------------------------------------
or buttons. Press the Hold button a second time to cancel the hold
-------------------------------
the or buttons
------------------------------
. When the hold temperature is
to permanently
the
the and buttons
Access Levels
The thermostat has two access levels: User and Installer. The Installer access level
provides access to all settings. The thermostat remains in the installer access level for
up to 24 hours after which it automatically changes to the user access level.
Once the thermostat has been installed, set the Lock / Unlock switch setting to Lock.
This hides the access level setting and prevents unauthorized changes to the thermostat
configuration settings.
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Troubleshooting
Error Messages
Error Message Description
SETUP MENU SAVE ERROR
The thermostat failed to read the Programmable Settings from memory
and has reloaded the factory default settings. The thermostat stops
normal operation until the access level is changed to Installer and all
Programmable Settings are checked. The thermostat continues to
provide freeze protection.
ROOM SENSOR OPEN CIRCUIT ERROR
The built-in air temperature sensor has an open circuit fault. Do not
confuse this error with the auxiliary room sensor short circuit error.
Room
Room
This error cannot be field repaired. Contact your wholesaler or tekmar
sales representative for details on repair procedures.
ROOM SENSOR SHORT CIRCUIT ERROR
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.
AUXILIARY SENSOR 1 OPEN CIRCUIT ERROR
The auxiliary sensor 1 has an open circuit. Check for loose or damaged
wires. Locate and repair the problem as described in the Sensor
Testing section of this brochure. The error clears after the auxiliary
sensor fault is corrected. If the auxiliary sensor was intentionally
removed, set access level to Installer and set Sensor 1 to None.
AUXILIARY SENSOR 1 SHORT CIRCUIT ERROR
The auxiliary sensor 1 has a short circuit. Check for damaged wires.
Locate and repair the problem as described in the Sensor Testing
section of this brochure. The error clears after the auxiliary sensor
fault is corrected.
AUXILIARY SENSOR 2 OPEN CIRCUIT ERROR
The auxiliary sensor 2 has an open circuit. Check for loose or damaged
wires. Locate and repair the problem as described in the Sensor
Testing section of this brochure. The error clears after the auxiliary
sensor fault is corrected. If the auxiliary sensor was intentionally
removed, set access level to Installer and set Sensor 1 to None.
AUXILIARY SENSOR 2 SHORT CIRCUIT ERROR
The auxiliary sensor 2 has a short circuit. Check for damaged wires.
Locate and repair the problem as described in the Sensor Testing
section of this brochure. The error clears after the auxiliary sensor
fault is corrected.
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Frequently Asked Questions
Symptom Look for... Corrective Action
The power supply transformer
may have limited VA capacity. A
transformer with a larger VA rating is
recommended.
Thermostat must be in Mode Heat in
order to provide heating.
Display powering
on and off.
Measure voltage at
wiring terminals R
and C.
Mode Off or Cool
Heat not on
Floor Max
Room is too
hot due to floor
Floor Min
heating being on
Cooling not on Mode Off or Heat
The floor has reached the maximum
operating temperature.
Lower the Set Floor temperature
setting.
Thermostat must be in Mode Cool in
order to provide cooling.
Technical Data
Programmable Thermostat 521 Two Heat or Heat-Cool (Includes Sensor 079)
Literature 521_A, 521_C, 521_D, 521_Q, 521_U
Control Microprocessor control. This is not a safety (limit) control
Packaged weight 0.6 lb. (290 g)
Dimensions 3-11/16” H x 3” W x 15/16” D (94 x 76 x 24 mm)
Enclosure White PVC plastic, NEMA type 1
Approvals Meets Class B: ICES & FCC Part 15, CE
Ambient conditions
Power supply 10 to 30 V (ac/dc), 50/60 Hz, 1.8 VA, Class 2
Relay 30 V (ac/dc) 2 A, Class 2 circuits
Sensor
– Included Slab Sensor 079
– Optional tekmar type # 070, 072, 073, 076, 077, 079, 084
Indoor use only, 32 to 122°F (0 to 50°C), RH ≤90% non-condensing
NTC thermistor, 10 kΩ @ 77°F (25°C ±0.2°C) ß=3892
Slab Sensor 079 10’ (3 m) wire
Dimensions
Enclosure
Approvals CSA C US
Operating range -58 to 221°F (-50 to 105°C)
Sensor
A Watts Water Technologies Company
3/16” OD x 1-1/2” (5 mm OD x 38 mm)
316 stainless steel, 10’ (3 m) 24 AWG, 300 volt PVC insulated Zipcord
NTC thermistor, 10 kΩ @ 77°F (25°C ±0.2°C) ß=3892
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Limited Warranty and Product Return Procedure
Limited Warranty The liability of tekmar under this warranty is limited. The Purchaser, by taking receipt
of any tekmar product (“Product”), acknowledges the terms of the Limited Warranty in effect at the time
of such Product s ale and acknowledges that it has read and understands same.
The tekmar Limited Warranty to the Purchaser on the Products sold hereunder is a manufacturer’s passthrough warranty which the Purchaser is authorized to pass through to its customers. Under the Limited
Warranty, each tekmar Product is warranted against defects in workmanship and materials if the Product
is installed and used in compliance with tekmar’s instructions, ordinary wear and tear excepted. The passthrough warranty period is for a period of twenty-four (24) months from the production date if the Product is
not installed during that period, or twelve (12) months from the documented date of installation if installed
within twenty-four (24) months from the production date.
The liability of tekmar under the Limited Warranty shall be limited to, at tekmar’s sole discretion: the cost of parts
and labor provided by tekmar to repair defects in materials and / or workmanship of the defective product; or to
the exchange of the defective product for a warranty replacement product; or to the granting of credit limited to
the original cost of the defective product, and such repair, exchange or credit shall be the sole remedy available
from tekmar, and, without limiting the foregoing in any way, tekmar is not responsible, in contract, tort or strict
product liability, for any other losses, costs, expenses, inconveniences, or damages, whether direct, indirect,
special, secondary, incidental or consequential, arising from ownership or use of the product, or from defects in
workmanship or materials, including any liability for fundamental breach of contract.
The pass-through Limited Warranty applies only to those defective Products returned to tekmar during the
warranty period. This Limited Warranty does not cover the cost of the parts or labor to remove or transport the
defective Product, or to reinstall the repaired or replacement Product, all such costs and expenses being subject to Purchaser’s agreement and warranty with its customers.
Any representations or warranties about the Products made by Purchaser to its customers which are different
from or in excess of the tekmar Limited Warranty are the Purchaser’s sole responsibility and obligation. Purchaser shall indemnify and hold tekmar harmless from and against any and all claims, liabilities and damages
of any kind or nature which arise out of or are related to any such representations or warranties by Purchaser
to its customers.
The pass-through Limited Warranty does not apply if the returned Product has been damaged by negligence
by persons other than tekmar, accident, fire, Act of God, abuse or misuse; or has been damaged by modifications, alterations or attachments made subsequent to purchase which have not been authorized by tekmar;
or if the Product was not installed in compliance with tekmar’s instructions and / or the local codes and ordinances; or if due to defective installation of the Product; or if the Product was not used in compliance with
tekmar’s instructions.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, WHICH THE GOVERNING LAW ALLOWS PARTIES TO CONTRACTUALLY EXCLUDE, INCLUDING, WITHOUT LIMITATION,
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, DURABILITY OR DESCRIPTION OF THE PRODUCT, ITS NON-INFRINGEMENT OF ANY RELEVANT PATENTS OR
TRADEMARKS, AND ITS COMPLIANCE WITH OR NON-VIOLATION OF ANY APPLICABLE ENVIRONMENTAL, HEALTH OR SAFETY LEGISLATION; THE TERM OF ANY OTHER WARRANTY NOT HEREBY CONTRACTUALLY EXCLUDED IS LIMITED SUCH THAT IT SHALL NOT EXTEND BEYOND TWENTY-FOUR (24)
MONTHS FROM THE PRODUCTION DATE, TO THE EXTENT THAT SUCH LIMITATION IS ALLOWED BY THE
GOVERNING LAW.
Product Warranty Return Procedure All Products that are believed to have defects in workmanship or materials must be returned, together with a written description of the defect, to the tekmar Representative assigned to
the territory in which such Product is located. If tekmar receives an inquiry from someone other than a tekmar
Representative, including an inquiry from Purchaser (if not a tekmar Representative) or Purchaser’s customers,
regarding a potential warranty claim, tekmar’s sole obligation shall be to provide the address and other contact
information regarding the appropriate Representative.
WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects
or other reproductive harm. For more information: www.watts.com/prop65
Product design, software and literature are Copyright ©2014 by tekmar Control Systems Ltd.,
A Watts Water Technologies Company. Head Offi ce: 5100 Silver Star Road, Vernon, B.C.
Canada V1B 3K4, 250-545-7749, Fax. 250-545-0650
All specifications are subject
to change without notice
28 of 28 521_D - 01/14.
Web Site
: www.tekmarControls.com
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