Viessmann VITODENS 100-W Installation And Service Instructions Manual page 33

Installation Examples
System Layout 4
Installation of heating circuits:
- radiator heating circuit (high
temperature circuit)
- underfloor heating circuit with 3-way
mixing valve (low temperature circuit)
- DHW production with the following
flow conditions:
The flow rate of the heating circuits is
greater than the maximum possible
water flow rate of the Vitodens 100
boiler.
The use of a low-loss header is
therefore recommended.
A low-loss header is available as an
accessory part.
The radiator heating circuit is supplied
by a circulation pump (field supplied).
The underfloor heating circuit is
supplied by a circulation pump installed
on site which is controlled by the
extension kit. The DHW pump is field
supplied.
Please note!
The use of a low-loss header is
recommended if the water flow rate is
less than 1.7 GPM / 400 ltr/h or more
than 6.2 GPM / 1400 ltr/h.
The low-loss header is available as
accessory part. See page 36 in this
manual for details on the low-loss
header.
(continued)
Note 1
Optional high limit safety control of
heating circuit E.
(During DHW production with DHW
terminal activated, the boiler supply
temperature will be set automatically
to 172ºF / 78ºC).
The heating system must be protected
from excessive temperature if no
automatic mixing valves are used or no
DHW priority is required.
After the DHW call for heat is satisfied,
there is a 20 second pump post-purge
time.
Maximum Flow Rates
Model WB1B
∆ ∆ ∆ ∆
t
Output
Btu/h
30 ºF rise (GPM)
35 ºF rise (GPM)
40 ºF rise (GPM)
Note 2
The heating circuit pump logic output
of the Vitotronic 050 is used to
energize the RT (room thermostat)
output of power / pump module.
Therefore, using a room thermostat in
series with RT (room thermostat) input
of the boiler will reduce unnecessary
calls initiated by the pump logic output
of the Vitotronic to the Vitodens 100
boiler (mixing valve heating circuit
only).
Note 3
During DHW call for heat, there is no
priority on mixing valve heating circuit.
10-26 10-35
83,000 108,000
5.5 ----
4.7 6.2
4.2 5.4
Boiler Connections
33