tekmar 284 Boiler Control - Manual (Page 11)

© 2014 284_D - 08/14 11 of 60 A Watts Water Technologies Company
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 & natural convection.
Baseboard (BASE)
A baseboard terminal unit is similar to a radiator, but has a low
profile & 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, & boiler minimum supply temperatures. The factory
defaults can be changed to better match the installed system.
Locate the Terminal Unit setting in the Setup menu.
Terminal Unit Boil DSGN Boil MAX *Boil MIN
High Mass Radiant 120°F (49.0°C) 140°F (60.0°C) 140°F (60.0°C)
Low Mass Radiant 140°F (60.0°C) 160°F (71°C) 140°F (60.0°C)
Fancoil 190°F (88.0°C) 210°F (99.0°C) 140°F (60.0°C)
Fin-Tube Convector 180°F (82.0°C) 200°F (93.5°C) 140°F (60.0°C)
Radiator 160°F (71.0°C) 180°F (82.0°C) 140°F (60.0°C)
Baseboard 150°F (65.5°C) 170°F (76.5°C) 140°F (60.0°C)
Boil MIN is only available if at least one boiler is set to non-
condensing. If all available boilers are set to condensing,
Boil MIN is not available & is hard-coded to OFF.
Room -------------------------------------------- --------------------------------------------
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 (21.0°C), & it can be adjusted for both the occupied &
unoccupied periods.
Outdoor Design ---------------------------------- ----------------------------------
The outdoor design temperature is typically the coldest outdoor
air temperature of the year. This temperature is used when
doing the heat loss calculations for the building & is used to
size the heating system equipment. If a cold outdoor design
temperature is selected, the supply water temperature rises
gradually as the outdoor temperature drops. If a warm outdoor
design temperature is selected, the supply water temperature
rises rapidly as the outdoor temperature drops.
Boiler Indoor ------------------------------------- -------------------------------------
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.
Boiler Design ------------------------------------- -------------------------------------
The boiler design supply temperature is the boiler water
temperature required to heat the zones at the outdoor design
temperature, or on the typical coldest day of the year.
(Default automatically changes based on terminal unit
setting)
Warm Weather Shut Down (WWSD)--------------- ---------------
Warm Weather Shut Down disables the heating system when the
outdoor air temperature rises above this programmable setting.
When the control enters into WWSD, WWSD is indicated in
the status field. WWSD is only available when the Application
Mode is set to RSET.
While in WWSD, the control will still operate to provide
Indirect Domestic Hot Water or Setpoint operation.