Viessmann B1HF - DHW Heating; External Heating Circuit Hook-Up (if Installed)

97
The burner, the circulation pump and the 3-way
diverter valve are started or changed over if the cylin-
der temperature lies 2.5 K below the set cylinder tem-
perature.
In the delivered condition, the set boiler water temper-
ature is 20 K higher than the set cylinder temperature.
If the actual cylinder temperature exceeds the set cyl-
inder temperature by 2.5 K, the burner shuts down and
circulation pump run-on begins.
Danger
Risk of injury due to increased DHW tempera-
ture.
Inform the system user of the risk from the
raised outlet temperature at the draw-off points.
■
Gas condensing system boiler:
If the set DHW temperature is set to over
60 °C
■
Gas condensing combi boiler:
If there are several draw-off events in quick
succession or several appliance calibration
processes
External heating circuit hook-up (if installed)
Note
Only in conjunction with weather-compensated opera-
tion.
■
Function:
–
If the external demand is active (plug 96 or digital
input on EM-EA1 (DIO) electronics module closed),
the heating circuit is supplied with heat.
–
If the external demand is inactive (contact open),
heat supply to the heating circuit ends (regardless
of the current set room temperature or the switch-
ing time).
!
Please note
There is no frost protection for the connec-
ted heating circuits.
■
Connection:
–
If only one heating circuit is hooked up, use con-
nection at plug 96: See page 26.
–
If multiple heating circuits are hooked up, connect
all contacts to EM-EA1 extension (DIO electronics
module) with the subscriber number. 1 (rotary
switch = 1).
See EM-EA1 extension installation instruc-
tions
Note
Perform the hook-up with subscriber number "1".
Function description
DHW heating
6167586
Functions