Optional Operating Control - Opentherm (Ot); Room Thermostat Connect - Viessmann Vitodens 100-W B1HA 26Vitodens 100-W B1HA 35Vitodens 100-W B1KA 35 Installation And Service Instructions Manual

Vitodens 100-W, B1HA series & B1KA Combi Installation/Service
Accessing Electrical Connections
Legend
A Viessmann outdoor temperature sensor (OTS) (field wiring)
B OpenTherm (OT) 0-10V (field wiring)
C Connection cable terminal
D Power supply
E Accessories 120VAC*
%
DHW tank temperature sensor or aquastat (field supplied)
(B1HA only)
* When using the operating methods 'operation without
room temperature thermostat' or 'weather compensated
operation without room temperature thermostat' a jumper
must be installed on terminal 96, refer to page 64.
Room thermostat connection OpenTherm (OT)
24VAC thermostats require a
field supplied switching relay to
OT connection (ie Taco SR501
or Honeywell RA889A-1001)
Legend
A Room thermostat (24VAC)
B Room thermostat (dry contact)
C Switching relay
Boiler control base
GAS PUMP FAN
Connect Room Thermostat
(Dry Contact) to OT
connection
B
A
C
OR
(continued)

Optional operating control - OpenTherm (OT)

What is OpenTherm (OT)?
The OpenTherm (OT) protocol is a point-to-point
communication system, which connects a boiler with a
room controller or other devices. The room temperature
feedback calculates a heating demand (water temperature
request) and transmits it to the boiler. The boiler will
adjust the heat input accordingly (low-high modulation).
Follow the installation instructions of the field supplied
operating controls.
% B1HA:
For Viessmann DHW tanks: Tank temperature

sensor (plug on the cable harness outside the control
unit - red connectors labelled "5").
Operation without DHW tank:

Set the set DHW temperature to"OFF".
Note: When connecting accessories observe the separate
installation instructions provided with them.
Refer to the Operating Instructions.
Control Connections
37