Vitodens 200-W, B2HB 19 to 35 Technical Data
9
5461 883 - 02
System Flow Rates
9
Heating Circuit / Boiler Pumps
Viessmann offers a variety of Grundfos heating circuit/
boiler pumps which meet typical Vitodens system
installation requirements (see “Heating circuit pump
(field supplied)” or “Boiler pump (field supplied)” in the
Installation Examples starting on page 28). See tables
below for recommended pumps. Refer to the graph
on page 8 for the proper waterside boiler friction loss
calculations. The following pumps have been selected
based on boiler heat exchanger head loss and boiler piping
to a low-loss header.
IMPORTANT
Pump selection must be based on accurate system flow
and pressure drop calculations (includes DHW sizing).
Model
B2HB 19
B2HB 26
B2HB 35
Flow rate
20ºF
r
t GPM (L/h)
6.4 (1453)
--
--
25ºF
r
t GPM (L/h)
5.1 (1163)
--
--
30ºF
r
t GPM (L/h)
4.3 (969)
5.9 (1332)
--
35ºF
r
t GPM (L/h)
3.7 (830)
5.0 (1142)
--
40ºF
r
t GPM (L/h)
3.2 (727)
4.4 (999)
5.9 (1328)
Flow limitation
GPM (L/h)
6.2 (1400)
6.2 (1400)
6.2 (1400)
Recommended boiler pumps
Grundfos UPS 15-58 (3-speed), Taco 0015, Wilo Star S 21 FX
Before using the following pumps for a DHW tank
application, find out the proper pressure drop through the
tank, the required temperature difference through the coil
and system piping head loss of the domestic hot water.
Low-Loss Header Application
Sizing of Low-Loss Header in a Residential Single-Boiler Application
*
1
For system
r
t < 20° F use low-loss header sizes for
r
t 20° F.
*
2
Low-Loss temperature sensor - is included with the boiler for use in a single boiler application.
Boiler
Model
No. of
Boilers
Boiler
Max.
Flow
Rate
GPM
(L/h)
Typical System Flow Rates
Viessmann
Low-loss
Temp.
Sensor
Required*
2
r
t
*1
°F
(°C)
20
(11.0)
25
(14.0)
30
(17.0)
35
(19.5)
40
(22.0)
B2HB
19
1
6.2
(1400)
System Flow
Rate
LLH Required
LLH Model
GPM
(L/h)
6.4
(1453)
Yes
80/60
5.1
(1163)
Optional
80/60
4.3
(969)
Optional
80/60
3.7
(830)
Optional
80/60
3.2
(727)
Optional
80/60
Included
B2HB
26
1
6.2
(1400)
System Flow
Rate
LLH Required
LLH Model
GPM
(L/h)
8.8
(1999)
Yes
80/60
7.0
(1599)
Yes
80/60
5.9
(1332)
Optional
80/60
5.0
(1142)
Optional
80/60
4.4
(999)
Optional
80/60
Included
B2HB
35
1
6.2
(1400)
System Flow
Rate
LLH Required
LLH Model
GPM
(L/h)
11.7
(2657)
Yes
80/60
9.4
(2126)
Yes
80/60
7.8
(1771)
Yes
80/60
6.7
(1518)
Yes
80/60
5.9
(1328)
Optional
80/60
Included
