Bosch Appliances Combi Boiler User Manual


 
Applications Manual Bosch Greenstar | 53
Bosch Thermotechnology Corp.
Data subject to change
2.11 System 11: Greenstar Heating Boiler
with zone pumps, relay panel, room
thermostats and DHW tank loading
Summary:
Single boiler with primary/secondary piping con guration
supplying three heating zones controlled by individual
zone thermostats and a pump relay panel. Outdoor reset
with FW200 controller mounted on the boiler. 3rd party
room thermostats used to communicate heat demands
from the zones.
This system does not feature constant circulation and the
zone circulators runs only when a heat demand is com-
municated by the room thermostat and shut off when the
heat demand goes away. It is similar to Systems 8 and 10
except that a pump relay panel is being used.
Primary/secondary piping isolates the system ow from
the boiler ow and prevents the system from in uencing
boiler performance.
This system works particularly well for installations with
other heat sources, e.g. wood stoves or signi cant solar
gain. Compared to systems with the FW200 installed in the
room that will throttle down the boiler output when the
room reaches its set point, in this setup the thermostat
will shut the boiler off.
This system can also be used with a combi boiler (see
system 6) instead of the indirect red DHW tank.
In detail:
This system runs on pure outdoor reset without room
feedback on the heating curve. The FW200 installed in the
boiler adjusts the heating curve (boiler supply tempera-
ture) according to outdoor temperature. The 3rd party
room thermostats turn the boiler and the zone pumps on
and off based on the conditions in the living space.
FW200 provides warm weather shutdown.
For temperature sensitive radiant oor applications install
a thermostatic tempering valve for overheat protection.
Required components:
Greenstar heating boiler.
FW200 controller in the boiler.
Primary/secondary piping and system pump.
Thermostatic mixing valve (optional - overheat
protection for temperature sensitive floors).
3rd party room thermostats with dry contact closure
in each zone.
Zone pump relay panel, e.g. TACO SR503 or similar.
Indirect fired DHW tank.
Tank loading pump of sufficient capacity.
Additional instructions:
See manufacturer’s installation and operating instructions.