Control Operations Guide
Bosch Buderus SSB255 | SSB399 | SSB512 Boilers
| 21
Bosch Thermotechnology Corp.
|
03.2018
Data subject to change
5.
Set System settings on Managing Boiler: There are a number of parameter
settings which only need to be set on the Managing boiler. Follow the steps
outlined in step 4 to access and adjust the following parameters within the
Managing boiler only:
Parameter #1 (CH Mode) – based upon the selected CH Mode,
set those parameters which apply to that CH Mode. See detailed
explanation of CH Modes and the list of those parameters which
specifically impact the operation for that specific CH Mode. You
will only set CH Mode and any parameter related to that CH Mode
of operation on the “Managing” boiler’s control.
—
CH Mode = “0”
Setpoint control of the boiler using dry contacts #11 &
#12
—
CH Mode = “1”
Outdoor Reset using ON/OFF control of the boiler using
dry contacts
(enable/disable on contacts 11 & 12 cascade
will operate based upon reset curve set on Managing Boiler)
—
CH Mode = “2”
Full outdoor reset with no heat demand
(Based on
Weather Setpoint and WWSD)
—
CH Mode = “3”
Permanent set point demand
—
CH Mode = “4”
Analog control (0-10Vdc) of set point temperature
Parameter #35 (DHW Mode) only if there is an indirect tank
connected to the system.
Cascade Parameters – See section Cascade Start and Stop
Sequence for a detailed explanation of the Cascade operation. It
is recommended to set the following Cascade Parameters for your
specifi c system requirements.
—
Parameter #72
Permit Emergency Mode – Set value to “YES” to allow
Emergency operation
—
Parameter #73
Boiler Address - Set Value to “1” on Managing boiler
—
Parameter #74
Emergency Setpoint – Set desired emergency supply
temperature
—
Parameter #75
Delay start Next Boiler – Recommended to increase value to
120
—
Parameter #78
Differential UP Stop All Boilers – Set Value to 10 degrees
6.
Parameters which should be set on all other boilers within the cascade:
Parameter #24 - Design Supply Maximum Limit - Maximum
temperature for individual boilers
Parameter #72 – Permit Emergency Mode – must be turned “ON”
on each invdividual boiler
Parameter #73 – boiler Address – Boiler address set to values 2
thru 16 – do not duplicate address on any two boilers
Parameter #74 – Emergency Setpoint – desired supply temp when
in Emergency Mode (if enabled)
