Hydraulic Connection; Installation Examples - Viessmann VITODENS 200-W Technical Data Manual

Installation

Hydraulic Connection

Installation Examples

Please note that in the following piping layout examples all pumps are field supplied.
IMPORTANT
The examples on the following pages depict possible
piping layouts of the Vitodens 200-W boiler equipped
with Viessmann System Technology.
For boiler and tank combinations, please install only
feasible combinations listed in the Viessmann Price List.
Please note that the following examples are simplified
conceptual drawings only!
Piping and necessary componentry must be field verified.
A low water cut-off (LWCO) must be installed where
required by local codes.
Proper installation and functionality in the field is the
responsibility of the heating contractor.
WARNING
If a DHW storage tank other than a Viessmann
Vitocell 100 or 300 tank is used, the installer must
verify proper operation of the Viessmann DHW tank
temperature sensor with the original manufacturer
of the tank. Viessmann strongly recommends the
installation of a temperature tempering valve in the
DHW supply line.
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Vitodens 200-W, B2HB 19 to 35 Technical Data
System design
Viessmann condensing boilers can generally be installed
in any pumped hot water heating system (closed system).
The circulation pump is an integral part of the appliance.
Minimum system pressure 14 psi (1.0 bar).
The boiler water temperature is limited to 180ºF (82ºC).
To minimise distribution losses, we recommend that
you size the heat distribution system to a max. flow
temperature of 158ºF (70ºC).
To reduce burner cycling in low energy houses with a
correspondingly low heat demand, we recommend the
use of a low loss header.
IMPORTANT
DHW supply and return piping between boiler DHW
connections and the Viessmann DHW tank connections,
shall be a minimum of 1" nominal pipe diameter (for
models B2HB 19 to 35) DHW connection outlet sizes
provided on the boiler and the DHW tank). This will
ensure the residual head of the field supplied pump is
fully utilized to overcome the resistance of the DHW heat
exchanger coil and to provide sufficient water flow to the
boiler heat exchanger.
In non-Viessmann DHW tank applications, perform, in
addition to the above, accurate calculations for DHW
tank coil pressure drop versus boiler pump (field supplied)
residual head to ensure sufficient water flow to the boiler
heat exchanger. Failure to heed the above instructions
may cause boiler short-cycling and inadequate DHW
supply.