tekmar 360 Mixing Control User Manual

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TERMINAL UNITS

When using a Characterized Heating Curve, the control requires the selection of a terminal unit. The terminal unit determines the
shape of the Characterized Heating Curve according to how the terminal unit delivers heat into the building space (refer to Essay
E 003). The 360 provides for selection between six different terminal unit types: two types of radiant floor heat, fancoil, fin-tuben
convector, radiator, and baseboard. When a terminal unit is selected, the control automatically loads the design supply temperature
(MIX DSGN), maximum supply temperature (MIX MAX) and minimum supply temperature (MIX MIN). The factory defaults are listed
below. To change defaults, refer to section B3. If a default has been changed, refer to Section A to reload the factory defaults.

High Mass Radiant (1)

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.
Default values: MIX DSGN = 120°F (49°C), MIX MAX = 140°F (60°C),MIX MIN = OFF

Low Mass Radiant (2)

This type of radiant heating system is either attached to the bottom of a wood sub-floor,
suspended in the joist space, or sandwiched between the sub-floor and the surface.
This type of radiant system has a relatively low thermal mass and responds faster than
a high mass system.
Default values: MIX DSGN = 140°F (60°C), MIX MAX = 160°F (71°C), MIX MIN = OFF

Fancoil (3)

A fancoil terminal unit or air handling unit (AHU) consists 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.
Default values: MIX DSGN = 190°F (88°C) MIX MAX = 210°F (99°C),
MIX MIN =100°F (38°C)

Fin-tube Convector (4)

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 to the space is dependant
on the supply water temperature to the heating element and the room air temperature.
Default values: MIX DSGN = 180°F (82°C) MIX MAX = 200°F (93°C), MIX MIN = OFF

Radiator (5)

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.
Default values: MIX DSGN = 160°F (71°C), MIX MAX = 180°F (82°C), MIX MIN = OFF

Baseboard (6)

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.
Default values: MIX DSGN = 150°F (66°C), MIX MAX = 170°F (77°C), MIX MIN = OFF

MIXING INDOOR (MIX INDR)

The MIX INDR is the room temperature used in the original heat loss calculations for the building. This setting establishes the
beginning of the Characterized Heating Curve for the mixing zones.

Section B3: Advanced

Terminal Unit

High Mass Radiant

(1)

MIX DSGN

MIX MAX

MIX MIN

120°F (49°C)
140°F (60°C)

OFF

140°F (60°C)
160°F (71°C)

OFF

190°F (88°C)
210°F (99°C)
100°F (38°C)

180°F (82°C)
200°F (93°C)

OFF

160°F (71°C)
180°F (82°C)

OFF

150°F (66°C)
170°F (77°C)

OFF

Low Mass Radiant

(2)

Fancoil

(3)

Fin-tube Convector

(4)

Radiator

(5)

Baseboard

(6)