Aprilaire 4640 Scale Control Insert 323613-751 Always verify the status chart

Always verify the status chart on the blower door after installation

It is intended for non-potable heating and storage applications

For contractors managing low-flow hydronic or process systems

Is this valve compatible with both Natural Gas and Propane units

streamlining installation in tight plenum spaces

Aprilaire 4640 Scale Control Insert 323613-751 Always verify the status chartMaintaining your whole home humidification system requires precision engineered components like the Aprilaire 4640 Scale Control Insert. This genuine Aprilaire replacement part is specifically designed to encase the humidifier water panel, serving as a structural U shaped insert that guides water flow and manages mineral accumulation. Constructed from durable, heat resistant polypropylene, the 4640 insert effectively captures heavy scale buildup and