Boiler Control Instruction & Operation Manual, Rev 1
Page
34
of 64
Setup & Tuning
Parameter Adjustment
Outdoor Reset Continued
Factory
Setting
Range /
Choices
Parameter and Description
0 Min
0 to 30 Min
Boost Time
When the Central Heat Setpoint is decreased by Outdoor Reset settings, the Boost Time
parameter is used to increase the operating setpoint when the space heat demand is not
satisfied after the Boost Time setting is exceeded. When heat demand has been “on”
continuously for longer than the Boost Time parameter the operating setpoint is
increased by 10°F (5.6°C). The highest operating setpoint from Boost Time is current
Central Heat Setpoint minus the Central Heat “Diff Above” setting. A setting of 0 seconds
disables this feature.
187 (ºF) 50 to 190 (ºF)
Central Heat Outdoor Boost Maximum Off Point
Maximum value the setpoint can reach due to boost function. Should be set to match
Central Heat Setpoint.
Press DOMESTIC HOT WATER
CONFIGURATION to adjust the following parameters.
Factory
Setting
Range /
Choices
Parameter and Description
0 Min
0 to 90 Min
DHW Priority Override Time
When Priority Time is greater than zero and Domestic Hot Water (DHW) heat demand is
“on” the DHW demand will take “Priority” over space heating demand. When the System
and Boiler pumps are configured as
“Central Heat (off DHW priority)” or “Central Heat,
Optional Priority
” then they will be forced “off” during Priority Time. Priority Time provides
“Priority Protection” time for the event of a failed or excessive long DHW demand. “Priority
Tim
e” is the time that the priority of the boiler will shift away from Central Heat to satisfy a
Domestic Hot Water call for heat.
180
50 to 190 (ºF)
DHW Setpoint
The Domestic Hot Water (DHW) Setpoint parameter is used to create a boiler water
temperature setpoint that is used when DHW heat demand i
s “on”. When the DHW heat
demand is not
“on” (the contact is open or not wired) this setpoint is ignored
170 (ºF)
50 to 190 (ºF)
DHW Time of Day (TOD) Setback Setpoint
The TOD setpoint is used when a time of day timer relay is wired to the Time Of Day
Controller Input. When setback i
s “on” the time of day setback setpoint shifts the DHW
setpoint to lower the DHW temperature and to save energy while building is in a reduced
room temperature mode.
10 (ºF)
3 to 29 (ºF)
DHW Off Hysteresis
The boiler stops when the water temperature rises
‘Difference Above’ degrees above the
setpoint.
5 (ºF)
3 to 29 (ºF)
DHW On Hysteresis
The boiler starts when the water temperature drops
‘Difference Below’ degrees below the
setpoint.
44
0 to 400
DHW P Gain
Proportional Gain value for Sequencer control modes. A larger gain value results in
tighter, more active, PID control. Gain is the primary PID modulation rate tuning
adjustment and provides the immediate modulation rate response. Pick a gain based on
the desired initial response. The burner modulation rate can oscillate if the Proportional
Gain is too large.
45
0 to 400
DHW I Gain
Integral gain value For Central Heat control Modes. A larger value makes the Integral
ramp in less time (i.e., faster). Integral is a secondary PID modulation rate tuning
adjustment that ramps the output over time (typically minutes). Based on the selected
Local PID P, select the corresponding (from above table) Integral value. Repeats per
minute between 0.5 and 2.0 are typical. The burner modulation rate can oscillate if
the Integral time is too large.
