Watts tekmar 294 User manual

Installation, Operation and Maintenance Manual
Smart Boiler Control 294
IOM-T-294
WARNING
!
Please read carefully before proceeding with
installation. Your failure to follow any attached
instructions or operating parameters may lead to the
product’s failure.
Keep this Manual for future reference.

2IOM-T-294 2205 © 2022 tekmar
Important Safety Information .........................3
Radio Frequency Statement .........................4
Installation .......................................5
Installation Location .............................5
Wiring Schematic ...............................6
Wiring Instructions ..............................7
Testing the Sensor Wiring .........................9
User Interface ...................................15
Power On ....................................15
Lock Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Home Screen .................................16
Status Icons ..................................16
System Inputs Screen...........................17
System Outputs Screen .........................17
Boiler Supply Chart Screen .......................17
Boiler Status List Screen .........................18
Boiler Status Carousel Screen.....................18
Boiler Hours or Cycles Screen.....................18
Menu Screen .................................19
Navigation....................................19
Menus .........................................20
Home Screen .................................20
Settings Menu..............................21-28
Schedule Menu................................29
Notifications Menu .............................30
Overrides Menu ...............................30
About Menu ..................................32
Help Menu ...................................32
Sequence of Operation ............................33
Heating Calls..................................33
Central Heating Operation........................33
Domestic Hot Water (DHW) Operation ..............35
System Setup and Operation .....................36
Constant Setpoint Operation......................38
Remote Setpoint Call ...........................39
tekmarNet®4 Call ..............................39
Boiler Operation ...............................40
Boiler Modbus Communication ....................42
System Operation ..............................43
Pump Operation ...............................46
Combustion Air Damper Operation .................46
Schedule.....................................47
Time Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Troubleshooting ..................................48
Errors and Alerts ............................48-50
Technical Data ...................................52
Limited Warranty and Product Return Procedure .........52
Table of Contents

IOM-T-294 2205 © 2022 tekmar 3
This is a safety-alert symbol. The safety alert sym-
bol is shown alone or used with a signal word
(DANGER, WARNING, or CAUTION), a pictorial
and/or a safety message to identify hazards.
When you see this symbol alone or with a signal
word on your equipment or in this Manual, be alert
to the potential for death or serious personal injury.
• It is the installer’s 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 per-
sonal injury or death.
• This control is not intended for use as a primary limit con-
trol. 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.
To avoid serious personal injury and damage to the equipment:
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
Important Safety Information
This pictorial alerts you to electricity, electrocution,
and shock hazards.
Double insulated.
This symbol identifies hazards which, if not
avoided, could result in death or serious injury.
This symbol identifies hazards which, if not
avoided, could result in minor or moderate
injury.
This symbol identifies practices, actions, or
failure to act which could result in property
damage or damage to the equipment.

4IOM-T-294 2205 © 2022 tekmar
This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part 15 of the FCC
Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in
a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used
in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment
in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his
own expense.
This device complies with part 15 of the FCC Rules and with Industry Canada license-exempt RSS standard(s). Operation is
subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any
interference received, including interference that may cause undesired operation.
The antenna used for this radio must be properly installed and maintained and must provide a separation distance of at least
7.9 inches (20 cm) from all persons.
Changes or modifications not expressly approved by the party responsible for compliance could void the user’s authority to
operate the equipment.
Le présent appareil est conforme aux CNR d’Industrie Canada applicables aux appareils radio exempts de license. L’exploitation
est autorisée aux deux conditions suivantes:
(1) l’appareil ne doit pas produire de brouillage, et
(2) l’utilisateur de l’appareil doit accepter tout brouillage radioélectrique subi, même si le brouillage est susceptible d’en compromettre
le fonctionnement.
Radio Frequency Statement

IOM-T-294 2205 © 2022 tekmar 5
Use a Phillips screwdriver to remove
the two screws on the cover.
Pull the front cover towards you. The
top of the cover will pivot on a hinge.
Remove the cover by releasing the
pivot hooks.
Mount the enclosure to a wall using
#6 wood screws in the four mounting
holes. Use screw anchors if drilling
into masonry.
Use the 24 knock-outs to install
connecting conduits and cabling to
the control.
To install the cover, hook the top
of the cover to the enclosure, then
pivot the bottom to shut.
Use a Phillips screwdriver to fasten
the two bottom screws.
When choosing the location for the control, consider the following:
• Keep dry. Avoid potential leakage onto the control.
RH 90% to 104°F (40°C).
Non-condensing environment.
• Do not expose to operating temperatures beyond 32-104°F
(0-40°C)
• Provide adequate ventilation.
• Keep away from equipment, appliances or other sources of
electrical interference.
• Provide easy access for wiring, viewing, and adjusting the
display screen.
• Mount approximately 5 ft. (1.5 m) off the finished floor.
• Locate the control near pumps and/or zone valves if possible.
• Provide a solid backing to mount the enclosure to. For
example: plywood, studs, etc
• Use the conduit knockouts provided on the upper, lower,
back and sides of the enclosure.
Installation
Installation Location

6IOM-T-294 2205 © 2022 tekmar
This section provides a wiring schematic for the control.
FCC ID: 2AHQR-11500A
Contains FCC ID:
2AC7Z-ESP32WROOM32E
QOQMGM12P0
Contains IC ID:
21098-ESPWROOM32E
5123A-MGM12P0
CAN ICES-3 (A)/NMB-3(A)
Class 2 Circuits
Boiler Mod:
Class 2 Circuits
Input Power:
115 V (ac) ±10%, 60 Hz, 9 W
Relays:
230 V (ac), 5 A, 1/3 hp
Calls:
24 V (ac) or Short
Operating Temperature:
32°F to 122°F (0°C to 50°C)
Use Copper Conductors Only
2827
Boiler 2
2625
Boiler 1
24
Ethernet
3029
Boiler 3
3231
Boiler 4
3433
Boiler 1
Enable
3635
Boiler 2
Enable
3837
Boiler 3
Enable
4039
Boiler 4
Enable
4241
Boiler 1
Pump/Vlv
4443
Boiler 2
Pump/Vlv
4645
Boiler 3
Pump/Vlv
4847
Boiler 4
Pump/Vlv
50
49
Comb
Air Relay
5251
System
Pump
5453
DHW
Pump
5655
Power
N
DANGER
DANGER
To Reduce the Risk of Electric
Shock - Do not connect to a
circuit operating at more than
150 volts to ground.
Pour réduire les risques
d'électrocution choc - ne pas
raccorder à un circuit
fonctionnant à plus de 150 V à
la terre.
L
54
Out Sens
76
Boiler
Sensor
98
DHW
Sensor
1110
Heat
1312
DHW
1514
Setpoint
1716
tN4
Boiler Bus
19 2018
+Gnd
Expansion
22 2321
ACB+Gnd
Boiler Modbus
231
Ref In Gnd
Pressure Sens
Mod
+Mod +Mod +Mod +
Call
+Call +Call +
EMS
+
H2061B
Smart Boiler Control 294
For product literature:
Pour la documentation
du produit:
Watts.com/tekmar
tektra 1150-01
Designed and assembled
in Canada
N
G
L
LNG LNG
LNG LNG
LNG
LNG
tN4 C -+Gnd -+Gnd
LNG
+-+-+-+-TT TT TT TT
Wiring Schematic
• Before wiring, ensure all power is turned off and take all
necessary precautions.
• Sensor wiring may be extended to a total length of 500
feet (152 m) using 18 AWG solid conductor wire.
• Strip all wiring to a length of 3⁄8in. or 10 mm for all terminals.
• A circuit breaker or power disconnect that provides power
to the control should be located nearby and clearly labeled.
• Refer to the current and voltage ratings at the back of this
brochure before connecting devices to this control.
• Only qualified personnel should install or service the control.

IOM-T-294 2205 © 2022 tekmar 7
Ref
Pressure
Sensor
In
23
Gnd
1
Pressure Sensor 088 (Terminals 1, 2, 3)
An optional Pressure Sensor 088 (sold separately) can connect to the 294 to provide pressure
monitoring for hydronic systems up to 150 psi (1034 kPa). The pressure sensor requires the installation
of a tee with a 1⁄8"-27 NPT port to be installed near the expansion tank.
• Connect the Red reference voltage wire to terminal 1.
• Connect the Green pressure signal wire to terminal 2.
• Connect the Black power common wire to terminal 3.
Remove
cover by
sliding
upwards
away from
the base.
To wire from
the back,
remove the
knock-out in
the sensor
base.
S1
S1
If using
conduit,
remove the
flexible plug
from the base
bottom.
S1
S1
Attach the
base to
the wall,
soffit or
electrical
box.
S1
S1
• The 070 can be mounted directly onto a wall with the
wiring entering through the back or bottom of the enclosure.
Do not mount the 070 with the conduit knockout facing
upwards as rain could enter the enclosure and damage
the sensor.
• In order to prevent heat transmitted through the wall from
affecting the sensor reading, it may be necessary to install an
insulating barrier behind the enclosure.
• The 070 should be mounted on a wall which best represents
the heat load on the building (a northern wall for most buildings
and a southern facing wall for buildings with large south
facing glass areas). The 070 should not be exposed to heat
sources such as ventilation or window openings.
• The 070 should be installed at an elevation above the ground
that will prevent accidental damage or tampering.
Outdoor Sensor 070 (Terminals 4, 5)
This section explains how to wire individual devices to the Smart Boiler Control 294.
Wiring Instructions
• Connect 18 AWG or similar wire to the two terminals provided
in the enclosure and run the wires from the sensor to the
control. Do not run the wires parallel to telephone or power
cables. If the sensor wires are located in an area with strong
sources of electromagnetic interference (EMI), shielded cable
or twisted pair should be used or the wires can be run in a
grounded metal conduit. If using shielded cable, the shield
wire should be connected to the Com terminal on the control
and not to earth ground.
• Replace the cover of the sensor enclosure.
• Connect the 2 wires from the outdoor sensor to the Out
Sens terminals on the 294 (terminals 4 and 5).
S1
S1
+
Outdoor
Sensor
-
5
4

8IOM-T-294 2205 © 2022 tekmar
+
-
EMS
+
Outdoor
Sensor
-
5
4
EMS Connection (Terminals 4, 5)
An Energy Management System (EMS) can be connected to the 294 to provide a target water
temperature. This signal replaces the outdoor air temperature sensor. Either a 0 to 10 V (dc) or
2 to 10 V (dc) signal may be used.
• Connect one wire from the EMS to the Outdoor (+) terminal 4.
• Connect a second wire from the EMS to the Outdoor (-) terminal 5.
A 0 - 20 mA signal can be converted to a 0 - 10 V (dc) signal by installing a 500 Ω resistor in
parallel between the Outdoor (+) and (-) terminals (4 and 5). The EMS Signal setting must be
set to 0-10.
A 4 - 20 mA signal can be converted to a 2 - 10 V (dc) signal by installing a 500 Ω resistor
in parallel between the Com (-) and EMS (+) In terminals (19 and 16). The EMS Signal setting
must be set to 2-10.
Mounting the Universal Sensors
These sensors are designed to mount on a pipe or in a
temperature immersion well.
The Universal Sensor should be placed downstream of a pump
or after an elbow or similar fitting. This is especially important if
large diameter pipes are used as the thermal stratification within
the pipe can result in erroneous sensor readings. Proper sensor
location requires that the fluid is thoroughly mixed within the
pipe before it reaches the sensor.
Strapped to Pipe
The Universal Sensor can be strapped directly to the pipe
using the cable tie provided. Insulation should be placed
around the sensor to reduce the effect of air currents on the
sensor measurement.
Immersion Well
If a Universal Sensor is mounted onto 1" diameter L type cop-
per pipe, there is approximately an 8 second delay between a
sudden change in water temperature and the time the sensor
measures the temperature change. This delay increases con-
siderably when mild steel (black iron) pipe is used. In general,
it is recommended that a temperature well be used for steel
pipe of diameter greater than 11⁄4". Temperature wells are also
recommended when large diameter pipes are used and fluid
stratification is present. If the well is not a snug fit on the sen-
sor tube, use the heat transfer paste. Apply paste to the sides
of the sensor and place a pea-sized globule on the sensor tip.
Push the sensor into the well and when it bottoms out, press
firmly. The paste will be forced up the sides of the well.
Conduit Connection
The Universal Sensor and Universal Sensor Enclosure 080
(sold separately) are specifically designed to mount onto a
3⁄8" ID temperature well that is supplied with an end groove.
To install the well, plumb a ‘tee’ into the pipe and fix the well
into the ‘tee’. The 080 enclosure has a 7⁄8" back knockout that
must be removed and fitted over the temperature well. The
Universal Sensor is then inserted into the well and the retaining
clip supplied with the enclosure is snapped onto the well end
groove. If the well has a threaded end, the installer must sup-
ply a standard threaded conduit retaining ring. The two wires
from the sensor are connected to the terminal block provided
in the enclosure. The other side of the terminal block is used to
connect wires from the control.
Bottom of
Enclosure 080
Universal
Sensor
Cable Tie
Sensor
Well
Retaining
Clip
Universal
Sensor

IOM-T-294 2205 © 2022 tekmar 9
Boiler Sensor (Terminals 6, 7)
The included Universal Sensor 082 can measure the boiler supply temperature of water coming from the boiler
system. This sensor should be installed on the supply pipe ahead of the tees supplying any loads.
• Connect the wires to the boiler sensor terminals 6 and 7.
DHW Sensor (Terminals 8, 9)
A DHW sensor is used to measure the temperature of a DHW tank. For indirect DHW heating, the DHW sensor
can be used instead of a DHW aquastat. For direct DHW heating, only the DHW sensor can be used to control the
temperature of the DHW tank. The DHW Sensor 078 is sold separately.
• Connect the wires to the boiler sensor terminals 8 and 9.
TEMPERATURE RESISTANCE TEMPERATURE RESISTANCE TEMPERATURE RESISTANCE TEMPERATURE RESISTANCE
°F °C °F °C °F °C °F °C
-50 -46 490,813 20 -7 46,218 90 32 7,334 160 71 1,689
-45 -43 405,710 25 -4 39,913 95 35 6,532 165 74 1,538
-40 -40 336,606 30 -1 34,558 100 38 5,828 170 77 1,403
-35 -37 280,279 35 229,996 105 41 5,210 175 79 1,281
-30 -34 234,196 40 426,099 110 43 4,665 180 82 1,172
-25 -32 196,358 45 722,763 115 46 4,184 185 85 1,073
-20 -29 165,180 50 10 19,900 120 49 3,760 190 88 983
-15 -26 139,403 55 13 17,436 125 52 3,383 195 91 903
-10 -23 118,018 60 16 15,311 130 54 3,050 200 93 829
-5 -21 100,221 65 18 13,474 135 57 2,754 205 96 763
0-18 85,362 70 21 11,883 140 60 2,490 210 99 703
5-15 72,918 75 24 10,501 145 63 2,255 215 102 648
10 -12 62,465 80 27 9,299 150 66 2,045 220 104 598
15 -9 53,658 85 29 8,250 155 68 1,857 225 107 553
A good quality test meter capable of measuring up to 5,000
kΩ (1 kΩ = 1000 Ω) is required to measure the sensor resis-
tance. 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 temperature using the thermometer and then
measure the resistance of the sensor at the control. The wires
from the sensor must not be connected to the control while
the test is performed. Using the chart below, estimate the
temperature measured by the sensor. The sensor and ther-
mometer 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.
Do not apply voltage to a sensor at any time as damage
to the sensor may result.
Testing the Sensor Wiring
Boiler
67
Sensor
DHW
89
Sensor

10 IOM-T-294 2205 © 2022 tekmar
DHW Call (Terminals 12, 13)
If the DHW sensor option is not used, a call for indirect domestic hot water can come from an aquastat connected
to terminals 12 and 13. The DHW Call can be volt free or up to 24 V (ac).
• Connect the DHW Call terminals 12 and 13 to the DHW tank aquastat.
Setpoint Call (Terminals 14, 15)
The setpoint call operates the boiler system to maintain a fixed setpoint temperature. The setpoint call should
respond to loads that do not change with outdoor conditions. The setpoint call can be volt free or up to 24 V (ac).
• Connect the setpoint call terminals 14 and 15 to the output terminals on a setpoint control or thermostat.
Central Heat Call (Terminals 10, 11)
A central heat call is required whenever the building requires heating. The heat call can be volt free or up to 24 V (ac).
• Connect the Central Heat Call terminals 10 and 11 to a switched heat demand.
• Typical heat calls are from a switching relay, zone valve control or thermostat.
• A permanent heat call can be created by installing a jumper wire between terminals 10 and 11.
Heat
10 11
+ Call -
Setpoint
14 15
+ Call -
DHW
12 13
+ Call -

IOM-T-294 2205 © 2022 tekmar 11
tekmarNet4 Boiler Bus (Terminals 16, 17)
tekmarNet4 (tN4) is a wired communication network for tekmar thermostats, setpoint controls and snow melting controls to
communicate to the boiler control. The network provides central heating calls, DHW calls and setpoint calls as a digital message
between tekmar devices. This optimizes the heating system to operate more efficiently compared to on/off calls.
• The tN4 devices connect to the Boiler bus on terminals 16 and 17. The connection is polarity sensitive.
• Connect terminal 16 (tN4) to the tN4 terminal on the device.
• Connect terminal 17 (C) to the C terminal on the device.
Boiler Expansion (Terminals 18, 19, 20)
Ethernet (Terminal 24)
Boiler Modbus®Communication (Terminals 21, 22, 23)
The control operates 4 on board boilers and is expandable in groups of 4 up to a
maximum of 16 through the use of boiler expansions. The control connects to the
expansion through a wired three-wire connection. The maximum bus cable length is
100 feet (30 m) using 18 AWG solid conductor cable.
• Connect terminal 21 (-) to the boiler expansion terminal 1 (-).
• Connect terminal 22 (+) to the boiler expansion terminal 2 (+).
• Connect terminal 23 (Gnd) to the boiler expansion terminal 3 (Gnd).
The control can connect to the Internet through Ethernet.
• Connect the Ethernet RJ-45 port on terminal 24 to the building Local Area Network
(LAN) router or network switch using Category 5 cable.
The control can connect to select boilers that have an available Modbus communication
port to read the boiler’s error and lockout codes. The supported boilers are listed in the
Sequence of Operation section of this manual.
Use an 18 AWG Shielded Twisted Pair (STP) cable to connect the control to each
compatible boiler. The 294 operates as the bus master, and the boilers are member
devices. All boilers must use the same data rate, data type, parity bit, start bit parame-
ters as boiler 1. Boilers 1 to 16 are sequentially addressed 1 through 16.
• Connect the A (-) terminal on the boiler to the Modbus A (-) terminal 21.
• Connect the B (+) terminal on the boiler to the Modbus B (+) terminal 22.
• Connect the ground terminal on the boiler to the Gnd terminal 23.
Daisy chain wiring is recommended when connecting to multiple boilers.
18 19 20
Gnd
-+
Expansion
123
Gnd
-+
Expansion
21 22 23
Gnd
-+
Boiler Modbus
AB Gnd
-+
Boiler 1
AB Gnd
-+
Boiler 2
AB
RJ45
294 294EXP

12 IOM-T-294 2205 © 2022 tekmar
Modulating Boilers (Terminals 25 to 32)
The control provides either a 0-10 V (dc) or a 4-20 mA output to each boiler. Polarity is important.
• Connect the control Mod (+) terminals 25, 27, 29, 31 to boilers 1, 2, 3 and 4 analog signal input
(+) respectively.
• Connect the control Mod (-) terminals 26, 28, 30, 32 to boilers 1, 2, 3 and 4 analog signal input
(-) respectively.
Some modulating boilers may also require a boiler on/off enable signal in addition to the
modulating signal. Please consult the boiler manual.
Modutrol IV
tekmar
B
R
W
+
-
tekmar
V9055
+
-
B
R
W
Modutrol IV™
0 - 135 Ω
Actuating
Motor
B
R
W
Mod +
-
Modutrol IV
tekmar
B
R
W
+
-
tekmar
V9055
+
-
B
R
W
B
R
W
V9055™
0 - 135 Ω
Actuating
Motor
Mod +
-
The 4 to 20 mA output can be converted to a 0 - 135 Ω
output for a Modutrol IV™ gas valve actuating motor using a
0 - 135 Ω tekmar Converter 005 (sold separately).
The 4 to 20 mA output can be converted to a 0 - 135 Ω
output for a V9055™ gas valve actuating motor using a
0 - 135 Ω tekmar Converter 005 (sold separately).
Boiler
Control
294
Boiler
Control
294
Modutrol IV™ and V9055™ are trademarks and products of Honeywell International, Inc.
Boiler Enable (Terminals 33 to 40)
A single stage condensing or non-condensing boiler is enabled through the TT contacts.
• For Boiler 1 connect the Boiler Enable terminals 33 and 34 to the boiler TT contacts.
• For Boiler 2 connect the Boiler Enable terminals 35 and 36 to the boiler TT contacts.
• For Boiler 3 connect the Boiler Enable terminals 37 and 38 to the boiler TT contacts.
• For Boiler 4 connect the Boiler Enable terminals 39 and 40 to the boiler TT contacts.
-
+
Boiler 1
25 26
+ Mod -
T
T
Boiler 1
33 34
Enable

IOM-T-294 2205 © 2022 tekmar 13
Boiler Pump / Valve (Terminals 41 to 48)
Boiler pumps or valves requiring up to 230 V (ac) 5 A, 1/3 hp can be switched through terminals 41
to 46. If a single power source is used for multiple pumps, ensure they are not tied together at any
point between the pumps and the control. For simplicity in wiring and troubleshooting, a separate
breaker for each pump is recommended.
For pumps:
•
Connect the power source line wire (L) to terminal 41.
• Connect a wire from terminal 42 to the pump Line In terminal.
• Connect the pump Neutral (N) to the power source neutral.
• Repeat for additional boiler pumps 2 (terminals 43, 44), boiler pump 3 (45, 46) and boiler pump
4 (terminals 47, 48).
• Ensure each pump is connected to earth ground.
N
G
L
L
NG
Ground
Boiler 1
75 76
Pump/Valve
C
R
R
C
Boiler 1
75 76
Pump/V
alve
For 120 V (ac) valves:
•
Connect the power source line wire (L) to terminal 41.
• Connect a wire from terminal 42 to the valve Line In terminal.
• Connect the valve Neutral (N) to the power source neutral.
• Repeat for additional valves 2 (terminals 43, 44), valve 3 (45, 46) and valve 4 (terminals 47, 48).
• Ensure each pump is connected to earth ground.
Combustion Air (C.A.) Damper (Terminals 49, 50)
A C.A. damper requiring up to 230 V (ac) 5 A, 1/3 hp can be switched through terminals
49 and 50.
For 24 V(ac) actuators:
• Connect the power supply red (R) to terminal 49.
• Connect a wire from terminal 50 to the R on the combustion air damper.
• Connect the C on the combustion air damper to the power source common C.
• For 120 V(ac) actuators:
• Connect the power Line (L) to terminal 49.
• Connect a wire from terminal 50 to the Line on the combustion air damper.
• Connect the neutral (N) on the combustion air damper to the power source common C.
C
R
R
C
Comb
49 50
Air Relay
For 24 V (ac) valves:
• Connect the power source Red wire (R) to terminal 41.
• Connect a wire from terminal 42 to the valve power terminal.
• Connect the valve power common to the power source common (C).
• Repeat for additional boiler valves 2 (terminals 43, 44), boiler valve 3 (45, 46) and boiler valve
4 (terminals 47, 48).
N
G
L
L
NG
Ground
Boiler 1
75 76
Pump/Valve

14 IOM-T-294 2205 © 2022 tekmar
Provide a 15 Amp circuit for the input power.
• Connect the 115 V (ac) line wire (L) to terminal 55.
• Connect the neutral wire (N) to terminal 56.
Input Power (Terminals 55, 56)
N
L
Power In
LN
55 56
N
G
L
L
NG
Ground
DHW Pump (Terminals 53, 54)
An indirect DHW pump requiring up to 230 V (ac) 5 A, 1/3 hp can be switched
through the DHW Pump terminals.
• Connect the line wire (L) to terminal 53.
• Connect a wire from terminal 54 to the pump L.
• Connect a wire from the pump N back to the power source neutral.
• Ensure the DHW pump is connected to earth ground.
Pump
DHW
53 54
System Pump (Terminals 51, 52)
A system pump requiring up to 230 V (ac) 5 A, 1⁄3hp can be switched through
terminals 51 and 52. For simplicity in wiring and troubleshooting, a separate
breaker for each pump is recommended.
• Connect the power source line wire (L) to terminal 51.
• Connect a wire from terminal 52 to the pump Line terminal.
• Connect a wire from the pump Neutral (N) back to the power source neutral.
• Ensure the system pump is connected to earth ground. N
G
L
L
NG
Ground
Pump
System
51 52

IOM-T-294 2205 © 2022 tekmar 15
• When first powered on, the tekmar logo appears
followed by the lock screen.
• By default the control is not locked and does not require
a passcode.
• Press “Tap to Unlock”, and enter your passcode if
necessary.
• When first powered on, the tekmar logo appears.
• If the display does not turn on, please contact your tekmar
sales representative or technical support for assistance.
• A custom passcode can be set through the Security
menu. This is an optional feature.
• If the custom passcode is lost, the master passcode
is 0294.
User Interface
Power On
Lock Screen

16 IOM-T-294 2205 © 2022 tekmar

ETHERNET
Blue indicates connection to Ethernet.
WI-FI
Blue indicates connection to Wi-Fi.
WATTS ONSITE
Blue indicates connection to the Watts®
OnSite cloud service.
SCHEDULE
Blue indicates the programmable schedule
is on.
tekmarNet®
Blue indicates communication with other
tekmarNet®devices.
EXP
EXPANSION
Blue indicates connection to a expansion
control for boilers 5 to 16.
NOTIFICATIONS
When displayed, it indicates an error or
warning notification is present.
Press to go to
Menu screen
Status icons
Error notification
Press to go to Boiler
Status
Press to go to Boiler
Supply chart
Swipe right to lock
screen
Swipe left to go to
system inputs and
outputs
EXP

Home Screen
Status Icons

IOM-T-294 2205 © 2022 tekmar 17
• When a call for heat is active, the dot is green.
• When there is no call for heat, the dot is gray.
• The central heating and setpoint targets are for the
boiler system.
• The Domestic Hot Water target may be for either the
DHW tank or the boiler system. This is determined by the
configuration settings DHW Type and DHW Sensor.
• The outdoor temperature can measured by a wired
sensor, through a sensor connected to a tekmarNet
device or through an Internet weather service.
• The domestic hot water tank sensor is optional and
is configured through the Settings > Heating Calls >
Domestic Hot Water > DHW Sensor setting.
• The pressure sensor is optional and is configured through
the Settings > System > Pressure Sensor setting.
• When an output is turned on (relay closed), the dot
is green.
• When an output is turned off (relay open), the dot
is gray.
• When Domestic Hot Water Priority is in effect, the dot
is green.
• When Warm Weather Shut Down (WWSD) is in effect,
the dot is green.
• Manual override are displayed. In normal operation the
override will display “AUTO”.
• The boiler supply chart updates once per second with
the newest temperature data on the right.
• The chart time span x-axis is approximately 10 minutes.
• The temperature range y-axis automatically scales based
upon the min and max boiler supply temperatures from
the last 10 minutes.
• The boiler target is visible when between the min and
max boiler supply temperatures from the last 10 minutes.
System Inputs Screen
System Outputs Screen
Boiler Supply Chart Screen

18 IOM-T-294 2205 © 2022 tekmar
• Press …ellipsis to go to the Boiler Status Carousel screen
• The circle in blue indicates the boiler firing rate percent or
boiler target temperature
• Press the boiler hour number to go to the Boiler Hours
screen
• Press the boiler cycle number to go to the Boiler Cycles
screen
• When the boiler pump is running or the boiler isolation
valve is open, the dot is green
• When the boiler pump is off or the boiler isolation valve
is closed, the dot is gray
•
Press to go to the Boiler Status List Screen
• Swipe left to view higher number boilers
• Swipe right to view lower number boilers
• The circle in blue indicates the boiler firing rate percent
or boiler target temperature
• Press the boiler hour number to go to the Boiler Hours
screen
• Press the boiler cycle number to go to the Boiler Cycles
screen
• When the boiler pump is running or the boiler isolation
valve is open, the dot is green
• When the boiler pump is off or the boiler isolation valve
is closed, the dot is gray
• Press CLEAR to zero the boiler hours or the boiler cycle
count
• Pressing CLEAR also saves the zero hours or cycles
• Zeroing the hours places the boiler to the end of the
boiler equal run time rotation sequence
Boiler Status List Screen
Boiler Status Carousel Screen
Boiler Hours or Cycles Screen

IOM-T-294 2205 © 2022 tekmar 19

BACK
Go back a level without saving
XHOME
Go to Home screen without saving
SAVE SAVE
Saves the new setting value
CLEAR CLEAR
Clears the boiler hours or cycles to 0
SKIP SKIP
Skip step in Setup Wizard or Wi-Fi Setup
BEGIN BEGIN
Begin the Setup Wizard
NEXT NEXT
Go to the next step
Menu Screen
Navigation

20 IOM-T-294 2205 © 2022 tekmar
Parameter Range Description
BOILER SUPPLY ---, -22 to 266°F
(-30 to 130°C)
Current boiler supply water temperature as measured by the boiler supply sensor. “---”
is displayed if there is a sensor fault.
BOILER TARGET ---, -22 to 266°F
(-30 to 130°C)
The boiler target is the temperature the control is trying to maintain at the boiler supply
sensor. “---” is displayed when no heat is required.
PLANT OUTPUT 0 to 100% The plant output is the combined firing rate of all the boilers together.
SYSTEM INPUTS
CENTRAL HEATING
TARGET
---, 50 to 230°F
(10.0 to 110.0°C)
Central heating target as determined by outdoor air reset. “---” is displayed if there is
not a central heating call.
DOMESTIC HOT
WATER TARGET
---, 50 to 230°F
(10.0 to 110.0°C)
Domestic hot water heating target. “---” is displayed if there is not a DHW call.
SETPOINT TARGET ---, 50 to 230°F
(10.0 to 110.0°C)
Setpoint heating target. “---” is displayed if there is not a Constant Setpoint or Remote
Setpoint call.
OUTDOOR
TEMPERATURE
SENSOR
---, -85 to 149°F
(-65.0 to 65.0°C)
Current outdoor temperature as measured by the outdoor sensor. “---” is displayed if
there is no sensor available or there is a sensor fault.
DOMESTIC HOT
WATER TANK
---, 32 to 266°F
(0.0 to 130.0°C)
Current indirect DHW tank temperature as measured by the DHW sensor. “---” is displayed
if there is no sensor connected or there is a sensor fault.
PRESSURE
SENSOR
0 to 150 psi
(0 to 1034 kPa)
Current system pressure as measured by the pressure sensor.
This item is only available if the Pressure Sensor is ON. “---” is displayed if there is no
sensor connected or there is a sensor fault.
BOILER 1 TO 16 STATUS
FIRING RATE 0 to 100%
Current firing rate of the boiler. Applies to all boiler types except when using the EMS
output signal.
TARGET
TEMPERATURE
50 to 230°F
(10.0 to 110.0°C)
Current temperature target of the boiler. Applies only to boilers using the EMS output signal.
HOURS 0 to 999999
hours
Counts the number of hours that the boiler has fired since the parameter was last cleared.
CYCLES 0 to 99999 cycles Counts the number of boiler cycles since the parameter was last cleared.
Menus
Home Screen