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Need replacement parts for this unit?
The Aprilaire 4181 scale control insert is commonly called a filter/pad frame. It is located on the inside of the humidifier, and surrounds the water panel. The purpose of the frame is to prevent mineral build-up inside the humidifier cabinet, and divert excess water to the drain. The scale control insert should be replaced every five to eight years - sooner if it is cracked or damaged. This item is also available as part of the maintenance kit for your model.
This item is compatible with the following Aprilaire model numbers.
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There are no compatible model numbers that match your entry.
Please note: Many replacement parts have subtle differences between them and can be easily confused. Attempting to install the incorrect part voids the return coverage. If you are not completely sure your order is correct please give us a call at 1-888-757-4774.
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This item is cost-prohibitive to ship on its own but is available to ship with orders over $200.
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