Greenheck Smoke Detector D4120 (Data Sheet) User Manual
Wire photoelectric duct smoke detector

Agency Listings
4-Wire Photoelectric Duct
Smoke Detector
The InnovairFlex
™
Series are the only duct smoke
detectors flexible enough to fit configurations from
square to rectangular and everything in between.
Features
Photoelectric, integrated low-flow technology
•
Air velocity rating from 100 ft/min to 4,000 ft/min (0.5 m/s to 20.32
•
m/sec)
Versatile mounting options: square or rectangular configuration
•
Plug-in sensor offers superb false alarm immunity and the latest
•
sensor technology
Broad ranges for operating temperature (–4°F to 158°F) and
•
humidity (0% to 95% non-condensing)
Patented sampling tube installs from front or back of the detector
•
with no tools required
Increased wiring space with a newly added ¾-inch conduit
•
knockout
One easy-access Test/Reset button and improved LED status
•
Patented interconnect feature for multi-fan shutdown
•
New high contrast terminal designations
•
Built-in short circuit protection from operator wiring errors
•
Field selectable settings for configuring the detector
•
Two DPDT Form-C relay contacts
•
24 VAC/DC or 120 VAC
•
Backward compatibility with existing Innovair products, including
•
remote accessories
The InnovairFlex D4120 4-wire photoelectric duct smoke 
detector features a pivoting housing that fits both square and 
rectangular footprints and mounts to round or rectangular ductwork. 
This unit senses smoke in the most challenging conditions, operating 
in airflow speeds of 100 to 4,000 feet per minute, temperatures 
of –4°F to 158°F, and a humidity range of 0 to 95 percent (non-
condensing). A plug-in sensor head offers improved false alarm 
immunity and simple installation, testing, and maintenance. An 
improved cover design isolates the sensor head from the low-flow 
feature for simple maintenance. 
The InnovairFlex housing provides ample wiring space, a ¾-inch 
conduit knockout, and built-in short circuit protection to prevent 
damage to sensitive components during installation. High contrast 
terminal designations make wiring easy. With its 2:1 sensor-to-power 
capability, the power board of the D4120 may be used to monitor 
a second sensor, D4S, simultaneously (i.e., supply and return side). 
As many as 50 InnovairFlex detectors can be interconnected. When 
one unit senses smoke, all interconnected detectors will switch 
their relays; only the detector sensing smoke will go into alarm, thus 
pinpointing the fire source. 
An easy-access Test/Reset button makes it possible to test the unit 
with the cover on. Three DIP switches can be used to configure field 
selectable settings: cover tamper delay, number of sensors to be 
controlled, and shut down on trouble option. Each power board 
has two LEDs that can be used to indicate the status of connected 
sensors, and a quick reference imprinted on the cover explains the 
LED status indications (Standby, Maintenance, Trouble, and Alarm). 
The InnovairFlex duct smoke detector can be customized to meet 
local codes and specifications without additional wiring. The new 
InnovairFlex product line is compatible with all previous Innovair 
models, including remote test accessories.
WARNING: Duct smoke detectors are NOT a substitute for open 
area smoke detectors; 
NOT a substitute for early warning detection;
NOT a replacement for a building’s regular fire detection system. 
Refer to NFPA 72 and 90A for additional information.
