Viessmann Vitodens 100-W Technical Data Manual page 13

Accessories for the Vitodens 100-W
Neutralization Unit for Single-Boiler
Applications
with neutralizing granulate
for Vitodens 100-W, WB1B 10-26, 10-35
Part No. 7134 231
310 mm
DN 40
Fig. 8
Low-Loss Header
–Type 80/50
Part No. 7134 791
(max. flow rate 17.6 GPM / 4 m
–Type 120/80
Part No. 7134 792
(max. flow rate 35.2 GPM / 8 m
Fig. 9
A low-loss header offers additional benefits
not provided by a pair of closely spaced
tees. Viessmann strongly recommends and
prefers the use of a low-loss header over
closely spaced tees. When used in
conjunction with the Vitodens 100-W boiler,
the low-loss header acts as hydraulic break,
decoupling boiler and system circuits from
each other (no sensor required). It is
recommended to use the low-loss header in
applications in which the total system flow
rate exceeds the maximum or falls below
the minimum flow rate of the Vitodens
100-W boiler. For maximum boiler flow
rates, see the table on page 9 in this
manual.
Viessmann strongly recommends the use of
a low-loss header in cases where the
system head and flow rates are unknown.
In addition, the low-loss header helps
eliminate air and debris [D] from the heating
system. See Fig. 10 and 11 for an
illustration of the principle of operation.
BS
TS
BY
3
/h)
3
/h)
BR
Fig. 10 Low-loss header design
T1
V
primary
T2
Fig. 11 Principle of Operation
Product does not look exactly as illustrated.
AB
SW
SS
SR
D
DV
T3
V T4 V
bypass secondary
T4
Vitodens 100-W Accessories
The low-loss header is available in the
following sizes. Select the size based on the
maximum system flow rate of your
application.
Model No. Max. system flow rate
Type 80/50 17.6 GPM / 4 m
Type 120/80 35.2 GPM / 8 m
Legend
AB Air Bleed
BR Boiler Return
BS Boiler Supply
BY Bypass (with laminar flow)
D Debris and/or air
DV Drain Valve
SR System Return
SS System Supply
TS Viessmann Temperature Sensor (not
used)
SW Sensor Well
T1 Boiler supply temperature
T2 Boiler return temperature
T3 System supply temperature
T4 System return temperature
V Boiler circuit flow rate
primary
V Heating circuit flow rate
secondary
V Bypass flow rate
bypass
Q Heat supplied by boiler
primary
Q Heat consumed by system
secondary
V < V
primary secondary
T1 > T3
T2 = T4
Q = Q
primary secondary
T1 ± 176°F / 80°C
V =V V
secondary primary+ bypass
IMPORTANT
When installing a low-loss header, system
mixed supply temperature (T3) must be
calculated as follows:
T1 × V +T4 V
primary bypass
T3=
V
secondary
3
/h
3
/h
13