Heating System Operation; Switching On; Switching Off - Viessmann VITODENS 100-W Operating Instructions & User's Information Manual

Operation

Heating System Operation

Outside temperature
Legend
A Selector dial "tr" setting: 1
B Selector dial "tr" setting: 2
C Selector dial "tr" setting: 3
D Selector dial "tr" setting: 4
E Factory default
F Selector dial "tr" setting: 5
G Selector dial "tr" setting: 6
10
Vitodens 100-W, WB1B Operating & User's Information

Switching ON

Room dependent control:
Outdoor temperature sensor not connected
With no outdoor sensor installed, the "tr" dial will
provide a constant temperature set-point for the boiler
based on the dial position selected.
Setting the dial between 1 and 6 will provide a set-point
value of 81º F to 178º F (27º C to 81º C) respectively.
The dot between 4 and 5 represents the factory default
set-point value of 140º F (60º C).
Weather dependent control
Outdoor temperature sensor connected
With the outdoor sensor connected, the boiler will
Factory default
automatically recognize the sensor and switch the set-
point dial operation from constant temperature calculated
to outdoor reset calculated.
Adjusting the "tr" dial will select the heating curve
corresponding with the heating curve chart. The set-
point will be calculated from the design boiler water
temperature associated with the heating curve selected,
and reset from the actual outdoor air temperature. Setting
the dial between 1 and 6 will select the corresponding
curve from the chart. The dot between 4 and 5 is the
factory default curve.
The display "tr" indicates when a heat request has
been made.
Note: Both the room dependent control and the outdoor

Switching OFF

Turn the selector dial "tr" to "0".
Note: If an external OpenTherm device is connected that
reset control strategies require a closed contact at
terminals RT to generate a call for heat to the
boiler.
Setting the dial to "0" places the boiler in freeze
protection mode regardless of the control option
selected or the contact position at RT.
controls the boiler water temperature, it can no
longer be adjusted using the selector dial "tr"