Question about Aprilaire 400 Humidifier

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Aprilaire 400 - Mesh Screen not wet

The mesh screen is not consistantly's only wet in places... There's enough water running through the system, the water just doesn't drip down in a uniform fashion that makes the entire screen wet. Any suggestions? This did happen after I took it apart and cleaned it and replaced the filter. I put it back exactly as it was, but now the water doesn't seem to drip down evenly enough on the mesh screen. Any ideas?

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Re: Aprilaire 400 - Mesh Screen not wet

Not happy either. I bought 3 Aprilaire 400 for my house (3 zones). I picked this style since I have attic installation and did not want to run drains. The first night I expected a major air quality improvement but no change in humidity. I have installed humidifiers before so I know the drastic improvement they make. So I watched for a season and still no humidity improvement. Absolutely nothing at all. Same exact observation as you all described. Only the bottom of the media was wet. I'm dissatisfied with Aprilaire 400. Do not buy! Since I installed humidifiers before and understand them I am converting the Aprilaire 400 to work like a Aprilaire 600. I simply unwired the float sensors, removed the floats/lid and using a knife cut some of the plastic cups so the water would drain well. I also cut open the plastic exit port some too so it wont clog from dust globs. I obviously added drains. HUGE RESULTS. On the very first cycle on the humidity in that zone went from 25 to 48. I am watching carefully. -GK

Posted on Jan 09, 2011

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