IBC DC 33-124

1-33
INSTALLATION
DC SERIES COMBI BOILERS DC 23-84, DC 29-106, DC 33-124, DC 33-160
1.9.4 Thermostat / Sensor Wiring
A Thermostat from a single zone heating system can be connected directly to the
controller’s terminals X4.6 and X4.7. Do not apply power to the X4 terminal strip.
The Outdoor Sensor is not required for the boiler to operate. If the outdoor sensor
is not connected, the boiler will assume that the outdoor temperature is 32°F /
0°C and operate at a target water temperature calculated based on 32°F / 0°C. If
outdoor reset functionality and the Summer Shut Down feature is required then
the Outdoor Sensor must be connected to X4.8 and X4.9. The Outdoor Sensor
is a 12K ohm thermistor type sensor. The sensor should be installed on the
exterior of the building on the north side. The sensor should be installed so that it
is not effected by any heat sources from the building such as a dryer or exhaust
fan outlet, relief air or combustion air grill above a window or door, or mounted
directly under a deck or soft overhang.
DHW Aquastat or 12KΩ sensor can be connected to the controller’s terminals
X4.9 and X4.10. Do not apply power to the X4 terminal strip.