Rated 3.7 out of 5 by 7
Rated 3.0 out of 5.0 by Fred Erroneous Product Description
The product description erroneously states that "It features 12 in. of thin, moisture-sensitive nylon ribbon wound around 3 bobbins to provide optimum control and reliable operation under changing ambient." If it were true, you wouldn't be able to mount the product on a wall!! In addition, the installation manual does not show a ribbon nor does it mention it. Likewise, I checked several packages of the product in Home Depot and none had a ribbon!!!!!!!!!!! Furthermore, a search of the Internet fails to mention any such ribbon. Ribbons were used in older models in which the ribbon was inserted into the air duct to sense the humidity level.
January 1, 2014
Rated 4.0 out of 5.0 by ryry9 -=*MUST CALIBRATE HUMIDISTAT*=-
The 8908B humidistat needs to be calibrated correctly. You might notice that when you turn the knob to set the desired level that it "clicks" on and off around the 10% mark or at least at a point that is nowhere close to the actual humidity level inside your home. The clicking is the point at which the humidistat thinks that the humidity is inside your home. You will need a secondary hygrometer to figure out the exact level your house is at now. Make sure you buy a semi decent one that will itself be calibrated correctly. After calling honeywell they told me there was no way to calibrate the h8908b so I needed to figure out a way myself.
To calibrate, take the humidistat of the wall or duct that you installed it on. On the back you will see a small white plastic bolt. There will be some red glue that you will need to scrape away to turn the bolt. I didn't need to scrape away all of it. Just enough so that the bolt would turn.
Turn the bolt a bit and then turn the set knob on the front. You will see that the clicking has changed a bit. Keep going until it turns on off around the actual humidity level inside you home.
Not sure why the calibration was so far off to begin with but this will definitely fix any issues you had with the humidity level your humidifier was throwing out.
November 13, 2014
Rated 4.0 out of 5.0 by cschanzle poor calibration, but otherwise seems ok
Very poor Chinese factory calibration, but luckily can be adjusted by turning the small white plastic bolt. Factory "off" indicated at ~11% when room was actually over 30%. Has a hysteresis of ~8-10% (i.e., on at 30%, off at 38%). Mine squeaks when dial is turned, sometimes making it hard to hear the on/off clicks. Simple one-wire circuit interrupt. I like the wide range and honestly, the adjustability to recalibrate over time. Relatively inexpensive.
February 4, 2013
Rated 5.0 out of 5.0 by Tomcat easy to install
unit is accurate and cost effective. I plan to install four more units for climate control in our production areas.
April 15, 2014
Rated 3.0 out of 5.0 by Bird poduct is good for the price.
the setting for humidity control do not match the actual humidity. Buy a humidity meter and adjust accordingly.
Other wise I have been happy with eh purchase.
January 22, 2014
Rated 3.0 out of 5.0 by john looks better than the old one and it does the job.
This is a replacement for an older model which i thought wasnt working, found out this wasnt the problem but it looks better so I kept it, it does the job.
January 14, 2014
Rated 4.0 out of 5.0 by VideoPapa Humidistat Replacement
This was a replacement for an identical model which was in service for 5 years. Installed easily and functions properly.
February 8, 2012