Appendix; Piping In Heating/Cooling Application - Viessmann VD2-320 Installation Instructions Manual

Appendix

Piping in Heating/Cooling Application

Heating/
Cooling Unit
Heating/
Cooling Unit
Heating/
Cooling Unit
38
Boiler
Supply
Water
Chiller
Boiler
Return
Vitorond 200, VD2 Series 320 to 1080 Installation
The boiler, when used in connection with a refrigeration
system, must be installed so the chilled medium is piped
in parallel to the boiler with appropriate valves to prevent
the chilled medium from entering the boiler.
The 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 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.
A metal tag should be attached to these valves
as to purpose.
IMPORTANT
In such a system, the circulating pump must be operated
from a separate on/off switch - not from the pump
aquastat on the boiler!