Aprilaire Humidifiers
Aprilaire whole-house humidifiers in three types: bypass flow-through models (400, 500, 600 and 620), fan-powered models (700, 720 and the self-contained 300) and steam humidifiers (800, 800LC, 801, 865 and 866). Most come in manual or automatic control versions. Choose by type and your home's size. Free shipping option available in Canada.
Browse all whole-house humidifiers, or find replacement Aprilaire water panels and Aprilaire steam canisters.
Aprilaire humidifier guide: type, size and control ▾
Bypass, fan-powered or steam
Bypass models use the furnace blower and a bypass duct, and run when the furnace fan runs. Fan-powered models such as the 700 and 720 have their own fan, so no bypass duct is needed. Steam models make their own steam, so they can add moisture when the furnace is not heating; they need a water line, a drain and a dedicated electrical supply. The 866 is ductless with a 5658 fan pack, and the 800LC is for low-conductive water.
Size and control
Titles mark models as small (500) or large (600, 620, 700, 720). Choose a larger model for a larger home. M and MK models use manual control; A, AK and K models are automatic, which adjusts humidity as the outdoor temperature changes and helps prevent window condensation.
Installation and upkeep
A whole-house humidifier connects to the ductwork, water supply, drain and wiring, so have a licensed HVAC technician install it. Replace the water panel at least once each heating season; steam models need a new canister from time to time.
