Boiler In Heating/Cooling Application - Viessmann Vitodens 200-W 19 WB2B Series Installation Instructions Manual

Boiler Connections
Installation Examples

Boiler in heating/cooling application

Fig. 32
Legend
Heating/Cooling unit
Spring-loaded flow check valve
Circulation pump
Safety header
with automatic air vent and
pressure relief valve
Expansion tank
Water chiller
Boiler circuit pump (field supplied)
38
(continued)
v2
v1
The boiler, when used in connection
with a refrigeration system, must be
installed ensuring the chilled medium is
piped in parallel to the boiler with
appropriate valves to prevent the
chilled medium from entering the boiler.
See illustration on the left.
The boiler piping system of a hot water
heating boiler connected to heating
coils located in air handling units where
they may be exposed to refrigerated air
circulation must be equipped with flow
control valves or other automatic
means to prevent gravity circulation of
the boiler water during the cooling
cycle.
Check installation instructions of the
chiller manufacturer carefully for
additional requirements.
Cooling season starts:
Close valve v1 and open valve v2.
Heating season starts:
Close valve v2 and open valve v1.
IMPORTANT
Viessmann strongly suggests that the
valves pictured above be labelled "v1"
and "v2".
IMPORTANT
In the above system, the circulating
pump must be operated from a
separate on/off switch, not from the
pump aquastat on the boiler control.