tekmar 260 Boiler Control User Manual
Page 6
Copyright © D 260 -
03/09
6 of 20
Section B2: Installer
OUTDOOR DESIGN (OUTDR DSGN)
The OUTDR DSGN is the outdoor air temperature that is the typical
coldest temperature of the year where the building is located. This tem-
perature is used when doing the heat loss calculations for the building.
If a cold outdoor design temperature is selected, the boiler supply tem-
perature rises gradually as the outdoor temperature drops. If a warm
outdoor design temperature is selected, the boiler supply temperature
rises rapidly as the outdoor temperature drops.
ROOM OCC & UNOCC (ROOM)
The ROOM is the desired room temperature for the boiler zones, and it
provides a parallel shift of the
Characterized Heating Curve. The room
temperature desired by the occupants is often different from the design
indoor temperature (BOIL INDR). If the room temperature is not correct,
adjusting the ROOM setting increases or decreases the amount of heat
available to the building. A ROOM setting is available for both the occu-
pied (Day) and unoccupied (Night) modes.
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 260 provides for selection between six different terminal unit types: two types of radiant floor heat, fancoil, fin-tube
convector, radiator and baseboard. When a terminal unit is selected, the control automatically loads the design supply temperature
(BOIL DSGN), maximum supply temperature (BOIL MAX), and minimum supply temperature (BOIL 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: BOIL DSGN = 120
°F (49°C), BOIL MAX = 140°F (60°C), BOIL 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: BOIL DSGN = 140
°F (60°C), BOIL MAX = 160°F (71°C), BOIL MIN = OFF
150
°F (66°C)
170
°F (77°C)
140
°F (60°C)
BOIL DSGN
BOIL MAX
BOIL MIN
Terminal Unit
190
°F (88°C)
210
°F (99°C)
140
°F(60°C)
High Mass Radiant
(1)
120
°F (49°C)
140
°F (60°C)
OFF
Low Mass Radiant
(2)
Fancoil
(3)
140
°F (60°C)
160
°F (71°C)
OFF
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)
Decreasing OutdoorTemperature
Increasing W
ater
T
emperature
BOIL INDR
N
or
m
al
De
sig
n
ROOM
Ac
tu
al
Te
mp
.
Decreasing Outdoor Temperature
Increasing W
ater
T
emperature
cold
BOIL INDR
BOIL DSGN
warm
OUTDR
DSGN