Other Wiring; Thermostat / Sensor Wiring - IBC EX Series Installation & Operating Manual

3.10.3 Other wiring

Danger
Do not connect sensors to "Therm" terminals. Overheating components can
result in serious personal injury and/or property damage.
Other optional low voltage connections to the control board include:
Two auxiliary Interlocks - for external safety devices as may be required by some
jurisdictions, such as an external low-water cutoff.
Contacts for indoor and outdoor temperatures sensors associated with reset
heating. A 10K ohm thermister (resistor dependent on temperature) for outdoor reset
sensing is supplied with the boiler for improved comfort and combustion efficiency.
One pair for a DHW tank sensor. Connect to "DHW S" (not the respective Therm.
1,2,3,4 location) and the boiler automatically detects and calls a smart DHW
routine.
One pair of contacts for remote secondary loop temperature control.
One pair (marked BoilerNet) for network connection – this is used for connecting
multiple IBC modulating appliances for autonomous staging.
The bottom pair of contacts (labeled 'External Control') receives a 0-10VDC
(default) or 4-20 mA signal from an external boiler controller for direct throttle control.
The boiler's own sensors act as high limits only. The user must enter maximum and
minimum boiler supply temperatures.
Note
Sensors connected to any sensor input contacts must be of the NTC
Thermister type with a resistance of 10,000 ohms at 77°F (25°C) and β = 3892.
We do not recommend using 3rd party supplied sensors. Compatible water
temperature sensors and outdoor sensors can be supplied by your IBC
distributor.

3.10.4 Thermostat / sensor wiring

Each of the four loads has dry contacts for thermostats as marked on the lower connector
strip (e.g., "Therm 1"). Gang lines from a multiple-zoned load (e.g., off the end-switches for
each radiant floor zone) present a common thermostat signal to the controller. Ensure that
there are no disturbing influences on the call-for-heat lines - for example, that there are no
coils to switch an air handler motor. Most power stealing thermostats can be connected
directly to the Therm terminals. Consult the Controller manual for more detailed
instructions.
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Section: Installation