# furnace humidifiers



## Mr_Butterworth (Jun 26, 2006)

Hello'
What is the difference between fan powered and bypass humidifiers.  I'm having a Carrier Infinity System installed and the dealers are recommending different humidifiers.  Is one better?
Thanks
Mr Butterworth


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## Square Eye (Jun 26, 2006)

I know what a fan powered humidifier is, but a bypass? 

Is that supposed to be called passive? 

Passive humidifiers install in the duct and only work when the heating unit's fan is on. I like diffrerent ones depending on where the ductwork is or how accessible it is. Under the floor, in a basement, passive. Under the floor in a crawl space, powered. 
My thought is that a duct system that is in a crawl space could condense more moisture inside it than a duct system in a temperature controlled environment like a basement. A fan powered humidifier would push the moisture on out of the ductwork where a passive system may condense and puddle in the ducts.

We all know that puddle ducks are best left outside.

Quack quack.


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