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Vitodens 200-W, B2HB 19 to 35 Technical Data
Accessories
Accessories for Vitodens 200-W
Low-Loss Header
(continued)
Use only a Viessmann supplied temperature sensor.
Do not use any other manufacturer’s temperature sensor.
Legend
AB
Air Bleed
BR
Boiler Return
BS
Boiler Supply
BY
Bypass (with laminar flow)
D
Debris
DV
Drain Valve
SC
Sensor Cable
SR
System Return
SS
System Supply
TS
Viessmann Temperature Sensor
SW
Sensor Well
When installing a low-loss header, the system mixed
supply temperature (T3) must be calculated as follows:
Legend
T1
Boiler supply temperature
T2
Boiler return temperature
T3
System supply temperature
T4
System return temperature
Vprimary
Boiler circuit flow rate
Vsecondary
Heating circuit flow rate
Vbypass
Bypass flow rate
Qprimary
Heat supplied by boiler
Qsecondary
Heat consumed by system
Vprimary < Vsecondary
T1 > T3
T2 = T4
Qprimary = Qsecondary
T1 167° F (75° C)
Vsecondary=VVbypass
IMPORTANT
IMPORTANT
Model No.
Max. system flow rate
Type 80/60
19.5 GPM (4.4 m
3
/h)
Type 120/80
35.2 GPM (8 m
3
/h)
Type 160/80
*1
44 GPM (10 m
3
/h)
Type 200/120 *
1
80 GPM (18 m
3
/h)
*1
Floor-mounted version (typically used for
multiple-boiler installations).
Low-loss header design
(Typical)
Principle of Operation
