Viessmann Vitodens 100-W Technical Data Manual page 9

Waterside Flow (boiler circuit)
The Vitodens 100-W is designed only for closed loop, forced
circulation hot water heating systems.
Pressure drop (primary circuit) of Vitodens 100-W
8
26
7
23
6
19.7
16.4 5
4
13.1
3
9.8
2
6.6
1
3.3
0
0
0 2.2
0 500
Flow rate (USGPM)
A low-loss header must be used when the system flow
rate exceeds the maximum or falls below the minimum
flow rate of the Vitodens 100-W boiler. An alternative
method may be used, such as primary secondary piping
using closely spaced tees. 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.
Please see page 13 for details.
Use standard friction loss method for pipe sizing.
Observe boiler maximum and minimum flow rate limitations. If system flow rate exceeds
boiler maximum flow rate (as stated on page 13) or if system flow rate is unknown, Viessmann strongly
recommends the installation of a low-loss header. See page 13 for low-loss header information.
Heating Circuit Pumps
Recommended heating pumps with Vitodens 100-W, WB1B 10-26, 10-35:
H Grundfos 15-58 (3-speed)
H
Taco 00R
or equivalent
Refer to the graph above for the proper
waterside boiler friction loss calculations.
4.4 6.6 8.8 GPM
1000 1500 2000 ltr. / hr.
IMPORTANT
Pump selection must be based on accurate
system flow and pressure drop calculations
(incl. DHW sizing).
Technical Data/Heating Circuit Pumps
9