DIGI MISTER Evaporative Duct Mounted Whole House Furnace Humidifier with 8 UV-C LEDs, Atomizing Cool Mist Variable Capacities for Homes and Offices up to 3500 sq. ft.

I have had the unit(s) for a little over a month. I wanted to wait and give some time to use them before I wrote this review. Units like this are used in large commercial systems, so it does not make sense that some company did not make a smaller unit like this for the home before now. I have 2 of them on 2 systems in my home. They work great. If you are someone that is installing this yourself, it is a straightforward, very simple install. The best advice I can give is to READ the User's Manual and follow it. The other is that the unit will work okay if you use cold water but works wonderfully if you use hot water. Simple physics. If you have a whole home water filter, this is not a problem. If you do not have one and have hard water, you might need to clean the nozzles more often. It does take a little run-time and adjustment of the unit to find the sweet spot for adjustment of the temperature on setting. The unit is set at 110 degrees from the factory, but on my smaller 60,000 BTU furnace, I have found that I needed to adjust that down to 97 degrees to achieve my desired humidity level. On my larger 100,000 BTU furnace, 103 degrees is the sweet spot. The manufacturer Unisys Technologies has great support via email and phone. I called, and a real human answered the phone and was very knowledgeable about the unit and a great help to me. If you have any questions, contact them. The unit has many advantages over traditional whole-home humidifiers, but water usage is the biggest. Unlike other whole home humidifiers, water is not running off and down the drain. Where I live, water is relatively inexpensive, but sewer is expensive, and they base my sewer rate on winter water usage. I think It is that way for most people. I am now using an average of 9 to 12 gallons of water daily for both units compared to 80 to 110 gallons daily with my old traditional humidifiers. The old ones were like having a small water leak. The difference in water usage is about $30 a month on my sewer bill, almost enough to pay for both units in the first year. I rarely write reviews, but I think this humidifier is worth doing so. However, I can not stress enough to use hot water. It will work with cold if that is all you can use but Hot water work so much more effectively. It was well worth the time I spent fine-tuning the unit(s) on temperature for the cost savings on my sewer. You might think that you should adjust the temperature on to the lowest temperature you can. DON’T. It needs to warm the nozzles, so the mist is fine, and you need the blower to move air before it comes on. Also, I found that I could adjust my blower off-setting for 3 minutes after the heat call stops. If you can do this on your system, you should. This will help ensure that all the moisture is out of your ductwork. As one other reviewer noted, this is not a set-it-and-forget-it product. No whole-home humidifier is. I have found that a stiff bristle toothbrush works well for cleaning the nozzles. I have cleaned the nozzles once in a month of use. They were working fine but replaced the air filters on the furnace(s) and cleaned the nozzles as preventative maintenance. One more thing, and not about this humidifier. If you have the normal 1" or 2" furnace air filters, you need to change them at least once a month. They are not meant to last 3 or 6 months. Changing them once a month or more often will keep good airflow and save you money in the long run. All in all, this is a great humidifier unit with wonderful customer support.

We live in a very dry climate, my wife is very sensitive to low RH, and I've been seeking a suitable alternative to the leaky, ineffective, and wasteful pad-based humidifiers I've installed previously. This seemed like a simple and novel alternative at a reasonable price-point, so I figured I'd give it a shot.My install was complicated by the fact that I had to first patch a much larger hole where the previous forced air humidifier was mounted, but once done, install was the initial install was straightforward. After activating it for the first time, however, I too witnessed the pooling of excess water others have reported.No surprise based on other reviews, and I don't really see how Unisys thinks this is avoidable in the first place--you're spraying water at unknown pressure into an unregulated system with variable airflow and temperatures. Of course it's not all going to evaporate all of the time!Anyway, I knew what I was getting into and mounted the unit directly above my AC coil, which sits inside of a pan with a drain for condensation, so any excess goes down the drain (and is far less wasteful than what I replaced). That said, I did have to spend some time baffling and caulking the ductwork to ensure that any excess water flowed into the pan.My previous humidifier included a pressure switch to detect when the blower is operating, so I re-purposed that as an additional safety precaution (now requires airflow + configured temp to activate). Should also allow me to use the unit year-round without fear of it running continuously.Minus 1 star for doing a rather poor job of disclosing or designing around what is (based on my experience and other reviews) a common problem, but the RH in our home has more than doubled up to 40%, so this device definitely works if you're willing to engineer around its shortcomings!

Very happy with the great deal of flexability the Digi-Mister DM538 provides. With previous misters I had to wire the unit to constantly mist when the fan was on as their temprature setting was not adjustable and was set way too high for my heating system. This caused a barrell under the airhandler to need emptying every week. The compleat adjustment options in the DM538 design eliminate the excess moisture. I have the misting start at 90* F. Now have very little "un-used mist". Started out with all 5 nozzles working. now down to one nozzle for outside temps above 30* F. If we are in for a cold spell with temps below 30* I add another nozzle, as it is so easy to do. 100% sattisifed with the DM538.