29
5784 568 - 18
Vitodens 100-W, B1HA/B1KA 26 to 125 Combi Installation/Service
Connections
Installation Examples
(continued)
Vitodens 100-W, B1HA 26, 35, 94, 125 with DHW
storage tank and one heating circuit
Maximum Flow Rates
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 controller (field supplied)
C
Heating
circuit
D
Heating circuit pump with room thermostat
connection (field supplied)
E
DHW storage tank
F
DHW tank temperature sensor
G
Closely spaced tees, 4x pipe Ø or 12 in. (305 mm)*
H
Expansion
tank
I
Outdoor temperature sensor (OTS)
*
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.
See page 35 for details.
IMPORTANT
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 an accessory part.
DHW supply and return piping between boiler DHW
connections and the Viessmann DHW tank connections,
shall be a minimum of 1 in. nominal pipe diameter
(irrespective of the ¾ in. 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.
Model B1HA
26, 94
35, 125
Output MBH
88
117
t
30ºF (17ºC) rise GPM (L/h)
5.9 (1332) 7.8 (1772)*
35ºF (19.5ºC) rise GPM (L/h)
5.0 (1142) 6.7 (1522)*
40ºF (22ºC) rise GPM (L/h)
4.4 (999)
5.9 (1328)
* Requires low loss header or closely spaced tees.