Other Wiring; Thermostat / Sensor Wiring - IBC EX Series Installation And 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 units 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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3.10.3 Other wiring