AprilAire 700 Whole-House Fan Powered Humidifier
- Up to 5,300 sq. ft. in tightly built homes
- 18 gallons per day capacity
- Built-in fan pulls heated air from the furnace
- Dual sensors: outdoor temperature and indoor humidity
- Automatic digital control included
- 40% to 60% target humidity range
- 15.5 pounds, 11.35 x 15.91 x 18 inches
- 5 year manufacturer warranty
Last refreshed Sep 8, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
An automatic whole house humidifier for homes with forced air heat, with sensors that adjust output on their own. It needs a furnace, a water line and wiring, so plan on an installation job.
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ASIN: B00R3FY6KAModel: 700Category: Humidifiers
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Overview
Not a tabletop unit, this AprilAire whole house model is an evaporative humidifier for forced air furnace systems. A built-in fan pulls heated air from the furnace through a water panel fed by piped water, and the humidified air travels through the ducts to every room.
Automatic control is the reason to buy: dual sensors read outdoor temperature and indoor humidity and adjust output on their own. It needs a forced air system, a water supply and wiring, so installation is a project. The listing also gives two different coverage figures.
Who it's for
Large, tightly built homes on forced air heat are where it belongs, set once and left alone. Homes with radiators, baseboard heat or no duct access cannot use it.
Pros and cons
- Whole home coverage through the ducts
- Dual sensors adjust output automatically
- Built-in fan moves furnace air through
- Digital control included
- Requires a forced air furnace
- Plumbing and wiring installation needed
- Coverage listed two different ways
Performance notes
Water flows by gravity from a top distribution tray over the water panel, and furnace air passing through picks up moisture by natural evaporation. The control reads both outdoor temperature and indoor relative humidity, then sets output to match. The humidified air reaches the rooms through the existing ducts.
Specifications
| Brand | Aprilaire |
|---|---|
| Model | 700 |
| Dimensions & fit | |
| Item Dimensions D X W X H | 11.35 x 15.91 x 18 inches |
| Item weight | 15.5 pounds |
| Capacity & performance | |
| Capacity | 18 gallons per day |
| Power & efficiency | |
| Voltage | 120 volts AC |
| Power Source | AC, 24 VAC transformer |
| Construction & materials | |
| Material | Plastic |
| Included components | |
| Included Components | Humidifier with built-in fan, 24 VAC transformer, automatic digital control with sensor, outdoor temperature sensor, saddle valve, solenoid valve, Model 35 Water Panel, installation instructions and template |
| Warranty & support | |
| Warranty Description | 5 year manufacturer |
| Other details | |
| Floor Area | Up to 5,300 sq. ft. (spec sheet: 4,200 sq. ft.) |
| Operation Mode | Evaporative, fan powered |
| Filter Type | Evaporative water panel, Model 35 |
| Control Type | Automatic digital control with dual sensors |
| Other Special Features Of The Product | Adjustable humidity control, auto shut off, digital display, humidistat, service filter indicator |
Frequently asked questions
What comes in the box with the AprilAire 700?
Installation instructions and template, the humidifier with built-in fan, a 24 VAC transformer, an automatic digital control with sensor, an outdoor temperature sensor, a saddle valve, a solenoid valve and a Model 35 Water Panel.
Does the AprilAire 700 need a forced air furnace?
Yes. It is an evaporative humidifier for forced air furnace systems, and its built-in fan pulls heated air from the furnace.
How does the AprilAire 700 decide how much to humidify?
Dual sensors monitor outdoor temperature and indoor relative humidity, and the automatic control responds to both.
Is the AprilAire 700 a portable humidifier?
No. It is a whole house unit that works with the furnace and ducts, and it is supplied by a water line through the included valves.