Troubleshooting - Johnson Controls - HE-69120NP-0 - HE-69130NP-0 - HE-69520NP-0 - HE-69530NP-0 - Sensors - HE-69xx0NP Series

HE-69xx0NP Duct Probe Humidity Element with Temperature Sensor Installation Guide

Product name
HE-69xx0NP Series
Document type
Installation Guide
Document revision
Revision date

Before you begin

If the Duct Probe Humidity element does not function correctly:


  1. Verify that the unit is mounted in a location that is away from drafts, moisture, and sunlight.
  2. Use a humidity tester with accuracy greater than the accuracy of the element, such as an optical dew point hygrometer, to determine the percent of relative humidity (RH). Make sure that the accuracy of the tester is ±2% between 20% and 80% for 2% models, and ±3% between 20% and 80% for 3% models.
    Note: The humidity tester and the element must sense the air at the same temperature. Before testing, wait 30 to 60 minutes for the tester to stabilize to ambient temperature and humidity. A temperature difference of as little as 1°F (0.6°C) can cause a difference in measured RH of over 2.5% RH.
  3. Calculate the percent of RH indicated by the element as follows:
    1. For 0 VDC to 10 VDC output, multiply the output voltage by 10. For example: 7.5 VDC x 10 = 75% RH
    2. For 0 VDC to 5 VDC output, multiply the output voltage by 20. For example: 3.5 VDC x 20 = 70% RH
    Note: ±0.9°F (±0.5°C) corresponds to an error of about ±2% RH at 25°C if RH is at a high level, for example: 70%.
  4. Compare the RH readings between the humidity tester and the element. If the difference is more than the sum of the acceptable errors, replace the humidity element.
  5. If the humidity output is lower than expected, check the position of the output jumper setting.