Questions on my Model 600 Aprilaire Humidifier...

Monday, September 26, 2011 by Aprilaire Team
Consumer question:

We purchased a home with a AprilAire 600 humidifier with a manual control panel. This past winter we noticed it would increase the humidity level as the temperature changed unless it was in the test mode. I was told by a HVAC company that there was a sensor outside that may have malfuntioned causing the problem. I recently noticed what looks like a sensor wired into the control panel that does NOT go outside.
1) Could this be the sensor?
2) If so, shouldn't this be outside to measure the outdoor humidity levels?
3) If it should be outside, how should it be mounted?

Aprilaires' response:

Thank you for contacting us with regards to your Aprilaire Model 600 Humidifier. These controls would have an outdoor Temperature sensor, but not an outdoor humidity sensor. It should be wired into the terminals labeled ODT and should either be mounted outside or inside a fresh-air intake duct within 3' of the outside wall. If it's going outside, it should be placed above any potential snow line, out of direct sunlight and away from any exhaust vents that might give it a false temperature reading. A manual control panel would not use an outdoor temperature sensor. An automatic control operating in a manual mode would have a blue tag wired to the ODT terminals and be labeled "Manual Mode."
Please let us know if you have any further questions.

Comments for Questions on my Model 600 Aprilaire Humidifier...

Wednesday, October 26, 2011 by jeffrey busuttil:
i have an aprilaire 600a humidifier with a digital t-stat.I'd like to sense the return air in the plenum duct rather then the stat on the this possible with this stat to put a remote duct sensor .If so what should i get

Leave a comment