FAQ: VAV has airflow, but 75F DPS is reading 0 CFM

When seeing this condition, check the following:

1. Verify that the green indicator light is blinking.
   
   1. If there is no indicator light, check the cable from the Smart Node to the DPS.
2. If the DPS has a sensor connected in Daisy Chain fashion downstream, ensure the Daisy Chain Switch is set to "On".
3. Check the air pressure tubing from the airflow cross and ensure the + and - sides are connected to the proper inputs on the DPS.

If these steps check out, try the following:

1. Unplug the 3-pin cable from the Smart Node, wait 10 seconds, then plug it back in.  After 5 minutes, check to see if there is a CFM reading.  If not, proceed to the next step.
2. If there is a sensor downstream, unplug the 3-pin cable from the Smart Node to the DPS, then plug the sensor cable direct into the Smart Node.

If the sensor reports normally, the DPS has failed.  If the sensor does not report normally, then the Smart Node has failed.

Contact your local 75F partner or 75F support:

888-612-7575

support@75f.io

For more information on the DPS, please follow this link:

DPS Overview and Installation