Dip Switches; Boiler Pump Post Purge; Boiler Pump Continuous Operation; Minimum Boiler Water Temperature Protection - Viessmann VITOTRONIC 100 Installation, Start-Up And Service Instructions Manual

Vitotronic 100, KW10B Installation, Start-up and Service
Switches
(continued)

DIP switches

DIP switch Position
1
S6
LON enabled
ON or OFF

Boiler pump post purge

When switch S6.2 is turned ON, a boiler pump post purge
of 4 minutes is active when a TT demand is removed or
when the internal outdoor reset function enters warm
weather shut down. In the OFF position, the boiler pump
will turn off immediately after the call for heat or entering
WWSD based on the outdoor reset function.

Boiler pump continuous operation

When switch S6.3 is turned ON, the boiler pump will
operate continuously. If the control is programmed for
internal outdoor reset functionality, the pump will shut
down when in WWSD for a period of more than 30
minutes. As soon as the outdoor temperature drops below
the WWSD setting, the pump will turn back on. The pump
will be enabled if the front mounted override switch is
turned ON.

Minimum boiler water temperature protection

When switch S6.4 is turned ON, the boiler pump which
is connected to the 20 output of the boiler control will
be turned off. When a boiler water temperature is below
the minimum, the boiler temperature pump operation is
sensed. This will assist in the rapid temperature increase
of the boiler as well as not allowing a continuous return
of low temperature boiler water back to the boiler.
Position Position
2 3
Boiler pump Boiler pump
post purge continuous
delay operation
ON - 4 min. ON - Enabled
OFF - No OFF - Disabled
delay (works on
TT only)
Position Position
4 5
Minimum OpenTherm
boiler temp. thermostat
pump
operation
ON - Enabled ON - Enabled
OFF - Disabled OFF - Disabled

OpenTherm thermostat enable

When switch S6.5 is turned ON, the OpenTherm functionality
is turned ON (should the OT thermostat be connected). When
switch S6.5 is left in the OFF position, there will be no data
exchange between the control and OT thermostat, while the
thermostat may have a display present.

Internal outdoor reset function

When switch S6.6 is turned ON, the internal outdoor
reset function is enabled. Rotary dials 4 and 5 are used
to select the slope and WWSD point respectively. When
switch S6.6 is left in the OFF position, the TT demand as
well as the A1 auxiliary contact functionality will provide
a call for heat.
Auxiliary contact function (A1)
When switch S6.7 is turned ON, the boiler temperature
set point is a function of the input potential. When switch
S6.7 is in the OFF position, a dry contact closure at A1
will generate a boiler temperature set point of 176 o F
(80 o C).
Staging of the boiler will take place. The boiler pump will
not be activated with this demand input. See page 25 for
additional operation information.
Start-up
Position Position
6 7
Internal Auxiliary
outdoor input
reset function
function
ON - Enabled ON - 0-10V
Boiler set
OFF - Disabled point
OFF - Override
boiler to
176 o F
(80 o C
External
dry contact
demand
23