H635EZ1 Humidifier Filter/Water Panel Assembly Replacement Kit for AprilAire Whole-House Humidifier Models: 600, 600A, and 600M

This water panel filter fit my AprilAire humidifier perfectly and was easy to install. It feels like a quality replacement and helps keep the unit running smoothly. Good value and I’d purchase again.

This fits more than AprilAire humidifiers. I've been using this water panel for several years on my Trane. They are all basically the same humidifier. If the measurements are good it'll work and they work well. They have a reasonable cost comparatively and come in a 2 pack.

Perfect fit and function.

Not too expensive and effective

This filter was easy to install and fit perfectly without any hassle. Once in place, it noticeably improved the performance of the humidifier, keeping the air more comfortable during dry weather. The build feels sturdy and well‑made, and it holds up well through the season without breaking down. It’s a straightforward replacement part that does exactly what it should, making maintenance simple and effective.

Perfect replacement. We still had our annual maintenance from a trained HVAC technician. The technician installed this filter for a fraction of the cost had we purchased the filter from the HVAC guy.

This APRILAIRE 35 FILTER was super easy to install. It FIT OUR HUMIDIFIER On furnace PERFECTLY like the correct puzzle piece. On our furnace, we monitor that alerts us if any leaks are detected in or on furnace and when I was using these, we’ve never had a problem with leakages. Our humidity level is always in the correct range which is very important, especially during winters where it can get very dry but these filters definitely help maintain a consistent level of the proper humidity needed.

For anyone tired of the expensive metal frame filter pads rotting out in their older Carrier humidifier with the built-in guides approximately 14" x 10-3/4" x 2-1/4" (similar to model 49FH024121 with filter 318518-761), this kit will fit with minor modifications. To get mine to fit, I trimmed off the half round tabs on the frame openings flush to the edge lip, cut off the protruding bottom spout flush, clipped off the top of the tube guide, and about 1/2" off the top of each of the internal guides in the humidifier box to allow the distribution part of the frame to sit below the lid. No issues with the fan, bottom and top lids, water valve, and no interference with the fan. It also has the benefit of fitting the opening better so it is likely to perform better with less air going around the pad instead of through it. Good luck and hope this helps someone else.