Didnt look to me like these were the same thing really as the DC humidistat. The first one had a manual control for choosing between humidify / de-humidify, and the second one had a not so dissimiliar function. Looked like neither had an automatic relay that switched back and forth between humidify and dehumidify. Too bad too... I've been lately musing around with the idea of finding an alternative to the DC system... at least for grands. Keeping tank water at 5 degrees C warmer then room temperature will provide all the local humidity you want, without pads to wick the water up to a warming element. This, and building it as a stand alone unit, would allow for a much larger tank, easier service, and less electronics to go bad. Probably a bit less expensive to market and sell as well. So, when you mentioned the <<compatable>> humidistat I got real interested :) Well... something will pop up.
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