Boiler Control Instruction & Operation Manual
Page
38
of
68
Setup & Tuning
Parameter Adjustment
Central Heat
Factory
Setting
Range /
Choices
Parameter and Description
180
50 to 190 (ºF)
Central Heat Setpoint
Target temperature for the central heat priority. Value also used by the outdoor air reset
function.
170 (ºF) 50 to 190 (ºF)
Central Heat 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 reset
curve to save energy while building is in a reduced room temperature mode. The reset
curve is shifted by the difference between the High Boiler Water Temperature and the
TOD Setback Setpoint. Any time of day timer may be used to provide the input to the
control TOD input. W hen connected, it allows boiler water setback cost savings.
10 (ºF)
3 to 29 (ºF)
Central Heat Difference Above
The boiler stops when the water temperature rises
‘Difference Above’ degrees above
the setpoint.
5 (ºF)
3 to 29 (ºF)
Central Heat Heat Diff Below
The boiler starts when the water temperature drops
‘Difference Below’ degrees below
the setpoint.
3
1 to 5
Central Heat Response Speed
This
parameter
adjusts the Central Heat temperature controller Proportion Integral
Derivative (PID) values. Higher values cause a larger firing rate change for each
degree of temperature change. If set too high firing rate
“overshoots” required value,
increases to high fire causing the temperature to exceed the
“Difference Above”
setpoint and cycle the boiler unnecessarily. Lower values cause a smaller firing rate
change for each degree of temperature change. If set too low, the firing rate response
will be sluggish and temperature will wander away from setpoint. Refer to
Table 11
for
PID values used by these selections.
Table 11:
Response Speed Adjustment Guidelines
Press
to adjust the following parameters.
