tekmar 262 Boiler Control Installation - Manual (Page 7)

7 of 36 Copyright © D 262 - 12/08
BOILER START (Boil STRT) (
RESET RATIO
)
The Boil STRT temperature is the boiler supply water temperature that the
heating system requires when the outdoor air temperature equals the
OUT STRT
air temperature setting.
OUTDOOR START (OUT STRT) ( RESET RATIO )
The OUT STRT temperature is the outdoor air temperature at which the
control provides the Boil STRT supply water temperature to the system.
OUTDOOR DESIGN (OUT DSGN)
(
RESET RATIO & CHARACTERIZED HEATING CURVE
)
The OUT DSGN is the outdoor air temperature that is the typical coldest
temperature of the year where the building is located. This temperature is
used when doing heat loss calculations for the building.
BOILER DESIGN (Boil DSGN)
(
RESET RATIO & CHARACTERIZED HEATING CURVE
)
The Boil DSGN temperature is the supply water temperature required to
heat the boiler zones when the outdoor air is as cold as the OUT DSGN
temperature.
BOILER MINIMUM (Boil MIN)
(
RESET RATIO & CHARACTERIZED HEATING CURVE )
The Boil MIN is the lowest water temperature that the control is allowed to
use as a Boil TRG
temperature. During mild conditions, if the 262 calculates
a Boil TRG temperature that is below the Boil MIN setting, the Boil TRG
temperature is adjusted to at least the Boil MIN setting. During this
condition, if the boiler is operating, the
Minimum pointer turns on in the LCD
while the Boil TRG or the Boil SUP temperature is viewed. If the installed
boiler(s) is designed for condensing operation, set the Boil MIN adjustment
to OFF.
BOILER MAXIMUM (Boil MAX)
(
RESET RATIO & CHARACTERIZED HEATING CURVE )
The Boil MAX is the highest water temperature that the control is allowed to
use as a Boil TRG temperature. If the control does target Boil MAX, and the
Boil SUP temperature is near the Boil MAX temperature, the
Maximum
pointer turns on in the LCD while the Boil TRG or the Boil SUP temperature is
viewed. At no time does the control operate the boiler(s) above 248˚F (120˚C).
WARM WEATHER SHUT DOWN (WWSD) OCC & UNOCC
(
RESET RATIO & CHARACTERIZED HEATING CURVE )
When the outdoor air temperature rises above the WWSD setting, the 262
turns on the
WWSD pointer in the display. When the control is in Warm
Weather Shut Down, the Boiler Demand pointer is displayed if there is a
demand. However, the control does not operate the heating system to
satisfy this demand. The control does respond to either a
DHW Demand
or a Setpoint Demand and operates as described in Section C.
BOILER SETBACK (SETBACK) ( RESET RATIO )
The boiler SETBACK is the amount that the boiler supply water temperature
is reduced when the 262 is placed into an
UnOccupied mode, using an
internal or an external setback as described in Section A. This setting is
only available if the
Reset Ratio DIP switch is selected and Setback / None
DIP switch is set to Setback.
BOILER INDOOR (Boil INDR)
(
CHARACTERIZED HEATING CURVE )
The Boil INDR is the room temperature used in the heat loss calculations
done for the building. This setting establishes the beginning of the
Charac-
terized Heating Curve for the boiler zones. This single setting replaces the
Boil STRT water temperature and OUT STRT air temperature settings used
by the
Reset Ratio.
Sequence, Section B1
Boil Max + 1/2 Boiler Differential
Boil Max - 1/2 Boiler Differential
Boil W
ate
r Te
mp
era
tur
e
Pointer On Pointer On
Boil MAX
Pointer On
Boil MIN
Boil Wat
er Te
mpe
ratu
re
Boil Min + 1/2 Boiler Differential
Boil Min - 1/2 Boiler Differential
70
(21)
90
(32)
110
(43)
130
(54)
150
(66)
170
(77)
190
(88)
Outdoor Air Temperature
Supply W
ater
T
emperature
210
(99)
-20
(-29)
0
(-18)
20
(-7)
40
(5)
60
(16)
80
(27)
Boil DSGN
Boil MAX
Boil MIN
OUT STRT
WWSD Unocc
Boil SETB
OUT DSGN
Boiler Reset
Ratio
WWSD Occ
Boil STRT
70
(21)
90
(32)
110
(43)
130
(54)
150
(66)
170
(77)
190
(88)
Outdoor Air Temperature
Supply W
ater
T
emperature
210
(99)
-20
(-29)
0
(-18)
20
(-7)
40
(5)
60
(16)
80
(27)
Boil DSGN
Boil MAX
Boil MIN
WWSD Unocc
Boil IND
OUT DSGN
Boiler Characterized
Heating Curve
WWSD Occ
50
(10)
Boil ROOM Occ
Boil ROOM UnOcc