tekmar 275 Boiler Control - Manual (Page 5)

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Terminal Unit Setting in Adjust Menu
Select the appropriate terminal unit in the adjust menu.
This will change the shape of the characterized heating
curve to better match the heat transfer properties of that
specific terminal unit.
Hydronic Radiant Floor (HRF1)
A heavy or high mass, hydronic radiant floor system. This
type of a hydronic radiant floor is embedded in either a thick
concrete or gypsum pour. This heating system has a large
thermal mass and is slow acting.
Hydronic Radiant Floor (HRF2)
A light or low mass, hydronic radiant floor system. Most
commonly, this type of radiant heating system is attached to
the bottom of a wood sub floor, suspended in the joist space,
or sandwiched between the subfloor and the surface. This
type of radiant system has a relatively low thermal mass
and responds faster than a high mass system.
Fancoil (COIL)
A fancoil terminal unit or air handling unit (AHU) consisting
of a hydronic heating coil and either a fan or blower. Air is
forced across the coil at a constant velocity by the fan or
blower and is then delivered into the building space.
Fin–tube Convector (CONV)
A convector terminal unit is made up of a heating element
with fins on it. This type of terminal unit relies on the natural
convection of air across the heating element to deliver
heated air into the space. The amount of natural convection
is dependant on the supply water temperature to the heating
element and the room air temperature.
Radiator (RAD)
A radiator terminal unit has a large heated surface that is
exposed to the room. A radiator provides heat to the room
through radiant heat transfer and natural convection.
Baseboard (BASE)
A baseboard terminal unit is similar to a radiator, but has
a low profile and is installed at the base of the wall. The
proportion of heat transferred by radiation from a baseboard
is greater than that from a fin-tube convector.
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 Terminal Unit setting in the
Adjust menu.
Terminal Unit BOIL DSGN BOIL MAX BOIL MIN
High Mass Radiant 120°F (49°C) 140°F (60°C) OFF
Low Mass Radiant 140°F (60°C) 160°F (71°C) OFF
Fancoil 190°F (88°C) 210°F (99°C) 140°F (60°C)
Fin-Tube Convector 180°F (82°C) 200°F (93°C) 140°F (60°C)
Radiator 160°F (71°C) 180°F (82°C) 140°F (60°C)
Baseboard 150°F (76°C) 170°F (77°C) 140°F (60°C)
Room Setting in Adjust Menu
The Room setting is the desired room air temperature,
according to the outdoor reset heating curve. The Room
setting parallel shifts the heating curve up or down to
change the target water temperature. Adjust the Room
setting to increase or decrease the amount of heat available
to the building. Once the heating curve has been set up
properly, the Room setting is the only setting that needs to
be adjusted. The default Room setting is 70°F (21°C), and
it can be adjusted for both the occupied and unoccupied
periods.