Review on 🏡 Aprilaire 400M Whole Home Humidifier, Manual Water-Saving Furnace Humidifier, High-Capacity Whole House Humidifier for Homes up to 4,000 Sq. Ft., in White by Elizabeth Fuentes

Disclaimer: I only installed the filter housing assembly and did not use the included controller, transformer or water valve. Instead I use my Ecobee4 for power and humidity control and also used a 1/4 turn tee valve on the water line. The first problem is that the installation instructions and wiring diagrams are very basic. This product isn't difficult to install if you have basic DIY skills, but it certainly didn't make things easy for you. In fact, I used Honeywell's humidifier manuals to better understand the situation. Second, while I was able to install the product and get it running at full capacity, I quickly encountered a problem on the first night. When I got home I found that water was dripping down the sides of the unit into the air ducts and onto the floor, but the overflow drain pipe was dry to the bone. The plastic water supply pipe to the water tank "crossed" the entire manifold bowl and straight into my air duct. I checked the water pressure and made sure the hose was in place and checked everything. Thought maybe the fan speed is too high, but he's on MED as usual. After 2 days of troubleshooting I finally found that the problem only occurs when the water solenoid valve opens while the HVAC fan is already running. At the same time, due to the pressure of the air vacuum, the water jet coming from the plastic hose "melted” into the upper part of the block, where the blind cover is located, and flowed directly through the tub into the outer casing of the block. Since the overflow is in the filter pan assembly and not in the body of the unit itself, all water simply exited the unit both inside and outside the channel. Water never had a chance to enter the overflow drain as it never entered the pan/filter assembly. Because the water never got into the bowl or hit the float switches, the water supply continued until the heating cycle was shut off and all the water was spilled. I tried almost closing the water valve and that helped, but it still happened from time to time and it reduced the amount of water available to the filter and reduced its efficiency. I finally decided to fix the problem myself and simply installed an "apron" or water trap by clamping a rounded piece of sheet metal in front of the pipe to prevent water from dripping into the unit's ceiling and through the tub. I know it's confusing, but Aprilaire can avoid this problem (though probably rarely) by placing the water supply tube down in the pan instead of horizontally. You should also put the bypass drain in a plastic housing rather than in the filter bowl itself. See photos and attachment for clarification. Since I installed the water flow blocker it has been performing like a champ.