tekmar 422 Universal Reset Module User Manual
Page 18

© 2007
D 422 - 08/07
18 of 32
Boiler Outdoor Reset
There is a water temperature and therefore a characterized 
heating curve for each communication bus. When using 
boiler temperature water to heat zones, the installer will 
be required to set a boiler characterized heating curve. 
This requires the tN4 DIP switch to be set to Boiler and 
the Boiler Sensor DIP switch set to Supply.
Boiler Terminal Unit Defaults
When a terminal unit is selected for boiler zones, the 
control loads default values for the boiler design, boiler 
maximum supply, and boiler minimum supply temperatures. 
The factory defaults can be changed to better match the 
installed system. Locate the Boiler Terminal Unit setting 
in the Adjust menu.
Mix 1 and Mix 2 Outdoor Reset
Each tN4 communication bus operates on a separate water 
temperature. Therefore a separate characterized heating 
curve is required for Mix 1 and, if the tN4 DIP switch is 
selected to Mix 2, for mix 2 as well.
Mix 1 and 2 Terminal Unit Defaults
When a terminal unit is selected for Mix 1 (or Mix 2), 
the control loads default values for the mix design, mix 
maximum supply, and mix minimum supply temperatures. 
The factory defaults can be changed to better match the 
installed system.
• 
• Locate the Mix 1 and Mix 2 terminal unit settings in the
Adjust menu.
Mix Characterized Heating Curve
Terminal Unit
Mix
Design
Outdoor
Design
Mix
Indoor
Decreasing Outdoor Temperatures
Increasing Mix T
e
mper
ature
Terminal Unit
BOIL DSGN
BOIL MAX
BOIL MIN
High Mass Radiant (1)
120°F (49°C)
140°F (60°C)
OFF
Low Mass Radiant (2)
140°F (60°C)
160°F (71°C)
OFF
Fancoil (3)
190°F (88°C)
210°F (99°C)
140°F (60°C)
Fin-Tube Convector (4)
180°F (82°C)
200°F (93°C)
140°F (60°C)
Radiator (5)
160°F (71°C)
180°F (82°C)
140°F (60°C)
Baseboard (6)
150°F (76°C)
170°F (77°C)
140°F (60°C)
Boiler Indoor Design
The boiler indoor design temperature is the indoor temperature 
the heating designer chose while calculating the heat loss for 
the boiler water heated zones. This temperature is typically 
70°F (21.0°C). This setting establishes the beginning of 
the boiler characterized heating curve.
• 
• Locate the Boiler Indoor Design setting in the Adjust
menu.
Boiler Design Temperature
The boiler design supply temperature is the boiler water 
temperature required to heat the zones on the typical 
coldest day of the year.
•
• Locate the Boiler Design setting in the Adjust menu.
Terminal Unit
MIX DSGN
MIX MAX
MIX MIN
High Mass Radiant (1)
120°F (49°C)
140°F (60°C)
OFF
Low Mass Radiant (2)
140°F (60°C)
160°F (71°C)
OFF
Fancoil (3)
190°F (88°C)
210°F (99°C)
100°F (38°C)
Fin-Tube Convector (4)
180°F (82°C)
200°F (93°C)
OFF
Radiator (5)
160°F (71°C)
180°F (82°C)
OFF
Baseboard (6)
150°F (76°C)
170°F (77°C)
OFF
Mix 1 and Mix 2 Indoor Design
The Mix 1 (or Mix 2) indoor design temperature is the indoor 
temperature the heating designer picked while calculating 
the heat loss for the building for the Mix 1 (or Mix 2) water 
heated zones. This temperature is typically 70°F (21.0°C). 
This setting establishes the beginning of the Mix 1 (or Mix 2) 
characterized heating curve. 
• 
• Locate the Mix 1 and Mix 2 Indoor Design settings in
the Adjust menu.
Mix 1 and Mix 2 Design Temperature
The Mix 1 (or Mix 2) design supply temperature is the mix 
supply water temperature required to heat the zones when 
the outdoor temperature is as cold as the outdoor design 
temperature. 
• 
• Locate the Mix 1 and Mix 2 Design settings in the Adjust
menu.
Boiler Characterized Heating Curve
Terminal Unit
Boiler
Design
Boiler
Indoor
Outdoor
Design
Decreasing Outdoor Temperatures
Increasing W
a
ter T
e
mperatures
