General Operation Settings - Bosch Buderus SSB399 Control Operations Manual

1 2 | Bosch Buderus SSB255 | SSB399 | SSB512 Boilers

4 General Operation Settings

Parameter
CH Mode
(parameter #1)
Pump Mode
(parameter #2)
CH Setpoint
(parameter #3)
System Pump Overrun
(parameter #4)
Boiler Pump Overrun
(parameter #5)
CH Hysteresis
(parameter #7)
Anti Cycle Period
(parameter #9)
Anti Cycle Temp. Diff erence
(parameter #10)
Ramp Delay Step Mod.
(parameter #11)
Max. Power Central Heating
(parameter #14)
Min. Power Central Heating/DHW
(parameter #15)
Table 8
Data subject to change
Set Central Heating (CH) Mode based upon the desired control strategy for the boiler. See pages 2 thru 7 of this
manual for a detailed explanation of each CH Mode.
Three diff erent pump modes may be selected for the boiler depending upon how the boiler is piped and how many
pumps are controlled by the boiler. Diagrams (Fig. 3,4,5) for the three diff erent pump modes are shown on the
following page.
Central Heating Setpoint only applies to CH Mode #0 ( On/Off using dry contacts) and CH Mode #3 (Permanent
set point demand). The value set for CH Setpoint will be the boiler supply water temperature (system supply for
cascade).
The amount of time in seconds the CH Pump contacts (#104 thru
for heat has ended. Default is 300 seconds (5 minutes). The parameter is adjustable from 0 seconds to 900
seconds in 10 second increments.
The amount of time in seconds the Boiler Pump contacts (#101 thru #103) will be energized after the demand for
heat has ended. Default is 300 seconds (5 minutes). The parameter is adjustable from 0 seconds to 900 seconds in
10 second increments.
The temperature diff erential used by the boiler to control the on/off function of the burner. The Central Heating
Diff erential applies to all CH Modes. If the target boiler supply sensor (system supply for cascade) registers a
temperature above the target by more than the value of the diff erential, the burner will turn off . The burner will not
turn on until the boiler supply (system supply for cascade) sensor value has fallen the same amount equal to the
diff erential below the target setpoint temperature.
The amount of time in seconds the boiler will wait before restarting. The parameter is adjustable from 10 seconds to
900 seconds in 10 second increments
In addition to the Anti Cycle Period (see above) the boiler will monitor the System Supply Temperature Sensor. If the
Anti Cycle Period is active and there is a pending call for heat, the Anti Cycle Period will be overriden, and the burner
will fi re, if the temperature at the Supply sensor drops a certain number of degrees prior to completing the Anti Cycle
Period. Default value for this parameter is 12.6°F. The parameter is adjustable from 0°F to 36°F.
Default setting for this parameter is "Disabled" but can be set to "Enabled". By enabling this parameter the boiler
follows a pre-defi ned set of modulation "steps". The boiler will begin operating at a 10% power level after ignition for
60 seconds. Once this time period has passed, should there still be a call for heat from the system, the boiler power
level will be increased +20%. Every 30 seconds thereafter the boiler power will be increased by an additional +20%
until the call for heat is either satisfi ed, or the boiler reaches the CH Setpoint (par.#3) + Hysteresis (par.#7), or the
boiler reaches 100% of it's maximum power level.
The Maximum burner power for Central Heating can be limited during operation. Default value is 100% and may be
adjusted down in 1% increments to 50%.
The Minimum burner power for Central Heating and DHW operation can be limited during operation. Default value is
1% power and may be adjusted up in 1% increments to 30%.
Control Operations Guide
Description
#106) will be energized after the demand
03.2018 | Bosch Thermotechnology Corp.