The Aprilaire 4089 is a compatible part for the following humidifier models:
The Aprilaire 445 Humidifier Pump Assembly 4089 is a replacement pump assembly for Aprilaire recirculating style humidifiers, specifically models 445, 445A, and 448. With this humidifier water pump assembly you will be able to have your Aprilaire humidifier operating at its optimal performance level without having to sacrifice indoor air quality. This pump assembly is low maintenance and is built from durable construction material for durability.
Aprilaire 445 Humidifier Pump Assembly 4089 specifications: