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PART#-31600075 LIT-SDD4000-HVAC-S INSTALL REV.A
4. Secure the probe to the duct with the provided #6 x 3/8” sheet metal screws.
5. In a location close to the probe attach the pressure switch in a vertical orientation. Bend
mounting bracket as needed to attain vertical positioning.
6. Connect the pressure sensor to the duct probe with the clear ¼” ID x 3/8” OD tubing
provided.
7. Attach the two press-on connectors at one end of the 25 foot 18 gauge wire provided
to the tabs on the pressure sensor in either order.
8. The cable from the sensor switch will be connected to the screw terminal connector on
top of the modified SDD4004. Connect like colors together at the connector (the red
wire on the cable to the side of the connector with the red wire from the machine) and
tighten securely with a fine slotted screwdriver.
9. IMPORTANT: Check that the “HVAC“icon on the 4004 display is shown when the HVAC
fan is on, and goes out when the Fan turns off. (if you are unable to switch the HVAC
off, temporarily disconnect the clear plastic tubing between the sensor probe and the
sensor switch to verify proper sensor operation). If the sensor (Part #9) is installed at
an angle off of vertical or is subject to vibration it will not properly report changes in
airflow. If it seems to always be indicating ON or OFF double check the installation
angle while observing the 4004 display.
10. Set up schedules on the SDD4004 machine as per the manual to establish scent event
times, intensities and other settings.