The plastic water distribution plate above the mess element pad has very little of the sand like particles left on it's water flow surface .Is that a problem that needs correcting?

Aprilaires' response:

Thank you for your email regarding the granular coating in the distribution tray of your model 440 Aprilaire® Humidifier.

This coating is designed to provide equal distribution of water to each opening in the distribution tray, assuring an even flow of water over the water panel. If the coating is removed, it is not necessary to purchase a new distribution tray. You can accomplish the same uniform performance by applying a small amount of liquid dishwashing detergent over the entire lower surface of the water distribution tray. This will break the surface tension of the water and allow equal flow through each of the openings, provided the unit is level. This information can be found on Page Two of the enclosed homeowner's manual.

During future annual servicing, continue to clean out the “V” openings as in the past, but do not scrape all the mineral scale off the bottom of the water distribution tray. The scale or lime deposit will provide the same wetting action as the granular coating and give even water flow over the Water Panel.