System Layout 2 - Viessmann VITODENSd 100-W Technical Data Manual

Vitodens 100-W, WB1B Technical Data

System Layout 2

Vitodens 100-W, WB1B 10-26, 10-35 with...
- DHW storage tank
- low-loss header
- one heating circuit
AV
PRV
Legend
AV Air vent
PRV Pressure relief valve
TPV Temperature and pressure relief valve
A
Vitodens 100-W gas-fired condensing boiler
B External boiler/DHW controller (field supplied)
C
Heating circuit
D
Heating circuit pump (field supplied)
E
DHW storage tank
F
DHW tank temperature aquastat or sensor
G DHW circulating pump (field supplied)
H
Low-loss header
K Expansion tank
L Primary pump (boiler circuit, field supplied)
with low-loss header only
IMPORTANT
Primary pump must pump into the boiler (as illustrated).
Note: The use of a low-loss header is recommended if the
water flow rate is less than 1.7 GPM (400 L/h) or
more than 6.2 GPM (1400 L/h).
The low-loss header is available as accessory part.
Maximum Flow Rates
Model WB1B
∆ t
Output Btu/h
30° F rise (GPM)
35° F rise (GPM)
40° F rise (GPM)
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
TPV
(irrespective of the ¾" DHW connection outlet sizes
provided on the boiler and the DHW tank).
This ensures that the head of the 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 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.
Installation
26 35
83,000 108,000
5.5 ---
4.7 6.2
4.2 5.4
21