Best Whole House Humidifiers: Top 5 Compared

TL;DR: The Honeywell HM750A delivers on‑demand steam humidification for up to 24,000 cu ft, packs a compact 533.4 mm depth, but its premium $1,067.99 price may limit budget‑conscious buyers.

The standout feature of the HM750A is its advanced electrode steam generation, which produces 22 GPD at 240 V (or 11 GPD at 120 V) while drawing 12 Amp. This on‑demand approach means you only use steam when humidity drops, and the unit’s automatic‑fill tank removes the need for manual water handling.

Compared with the four other models in this roundup, the HM750A is the heaviest at 18.7 lb, outmatching the AprilAire 720A (13.75 lb) and the Honeywell HE400A (11.5 lb). Its depth of 533.4 mm also exceeds the AprilAire’s 16.5‑inch profile and the Honeywell Whole‑Home’s 470 mm depth, giving it a more substantial footprint. However, its coverage area—up to 24,000 cu ft—surpasses the AprilAire’s 6,250 sq ft rating and the Honeywell HE400A’s “up to 18,000 cu ft” claim, positioning it as the most capable unit for larger homes.

User feedback highlights the unit’s compact design and the convenience of the automatic‑fill system, which many reviewers say simplifies installation for a single installer. Professional reviewers note the self‑diagnostic tool as a time‑saver when troubleshooting. On the downside, customers point out that the pre‑mineralized cylinder needs annual replacement depending on water quality, and the system requires water conductivity between 125‑1200 µS/cm to operate properly.

Additional technical context includes ENERGY STAR certification, a static pressure rating of 2 inch WC, and a recommended service life of 10 years. Power consumption is listed at 1.5 kW on 120 V and 3.0 kW on 240 V, aligning with the on‑demand steam design to keep energy use in check.

Best for: Those prioritizing quality and willing to pay for premium performance — the Honeywell HM750A offers Depth: 533.4 mm

Avoid if: You're shopping on a tight budget — it's priced at $1,067.99

TL;DR: The AprilAire 720A humidifies up to 6,250 sq ft with a 21 gallon‑per‑day capacity, saves up to 15,000 gallons of water yearly, and packs premium features in a compact, reversible‑fan design.

What really sets the 720A apart is its 21 gallons per day humidification capacity on high fan speed and a coverage claim of 6,250 square feet. The HydroCore L panel delivers twice the evaporative efficiency of the older 700 series, and the system promises up to 15,000 gallons of water savings per year while cutting wastewater by 60%.

Compared with the four Honeywell models in this roundup, the 720A reaches far beyond the typical coverage range of 1,500‑4,000 sq ft. Its moisture output of 21 gallons per day also exceeds the 17‑gallon maximum of the Honeywell Whole Home unit. At 13.75 lb, it’s a bit heavier than the Whole Home (12.5 lb) and the HE400A (11.5 lb), but lighter than the HM750A (18.7 lb). Its 16.5‑in depth and 18.0‑in height make it taller and deeper than the TrueEASE (10.13‑in depth) and HE400A (10.1‑in depth), yet it still fits comfortably in most mechanical rooms.

Reviewers consistently praise the quick ~60‑second maintenance cycle and the reversible fan that can be set vertical or horizontal, which technicians say reduces service callbacks. Professional installers note that the floor‑drain requirement and the need for a dedicated HVAC duct connection are the main trade‑offs, especially for DIY‑oriented homeowners.

Best for: Large homes needing whole‑house humidification, especially those with central HVAC ducting and a desire for high capacity and water‑saving performance — the AprilAire 720A covers 6,250 square feet.

Avoid if: You lack central ductwork, prefer a DIY installation, or are working with a tight budget.

TL;DR: The Honeywell TrueEASE humidifier covers up to 20,000 cu ft, delivers 17 gallons/day, and saves up to 30 % water in a compact design, all for $212.92.

With a maximum building size of 20,000 cubic feet and a nominal capacity of 17 gallons per day, the TrueEASE is sized for large homes. Its water‑saving claim of up to 30 % less usage helps lower utility bills.

At 13.0 lb, the TrueEASE sits between the lighter Honeywell HE400A (11.5 lb) and the heavier Honeywell HM750A (18.7 lb). Its depth of 10.13 in matches the HE400A, while its height of 17.16 in is taller than both the Whole Home model (16.25 in) and the HE400A (15.0 in). The 15.0‑in width makes it wider than the Whole Home’s 9.75 in but narrower than the HE400A’s 17.15 in. Compared with the AprilAire 720A, the TrueEASE is slightly lighter and a bit shorter, yet still offers comparable capacity.

Professional reviewers note the snap‑into‑place bypass and slide‑out pad design cut installation time, and the included HumidiPRO digital humidistat provides automatic mode default 35 % RH with a 20‑60 % range. However, the lack of an automatic bypass closure can let extra heat escape, and the unit depends on the furnace fan running regularly, which may limit performance in homes with intermittent airflow.

Control flexibility includes a manual humidity range of 10‑90 % and a high‑temperature shut‑off set at 65 °F (adjustable 40‑90 °F). The dehumidifier compressor lockout can be set from 0 to 5 minutes, and the device runs on 0.5 A at 24 VAC, keeping power draw modest.

Best for: Buyers in the budget price range seeking the best quality at that price point — the Honeywell TrueEASE offers Water Savings: Up to 30% less

Avoid if: You need powerful performance or professional‑grade features

TL;DR: The Honeywell HE400A delivers up to 17 gal/day of moisture for homes up to 4,000 sq ft, packs a compact 10.1‑in depth, and costs $170.99, making it a solid budget whole‑house humidifier.

The HE400A can humidify up to 18,000 cu ft (2,000–4,000 sq ft) and pushes 17 gallons per day through its evaporative pad. A digital humidistat with an outdoor sensor lets you set humidity between 10%–90%, while the unit automatically shuts off when the target is reached. At 11.5 lb it’s light enough to handle during installation, and its 10.1‑in depth helps it fit into tighter bypass ducts.

Compared with the other four models, the HE400A is the lightest (11.5 lb vs. 13 lb‑plus for the TrueEASE, Whole Home, AprilAire and HM750A) and the shallowest (10.1 in depth versus 10.13 in for TrueEASE and well over 16 in for the others). It covers a broader footprint than the Honeywell Whole Home Humidifier’s 1,500–3,000 sq ft range, though the premium AprilAire 720A reaches a larger 6,250 sq ft. Price‑wise it sits below the TrueEASE and well under the AprilAire and HM750A, positioning it as the most budget‑friendly option in the set.

Professional reviewers highlight the high output and the outdoor‑sensor humidistat as energy‑saving strengths, noting that the unit only draws a maximum of 0.75 A. Users, however, repeatedly point out that installation demands duct access, a water line, and a floor drain, which limits DIY suitability. Seasonal pad replacement is required to keep performance up, and the system relies on the furnace’s fan cycle rather than a built‑in blower or tank‑empty alert.

Additional technical details include a calibration range of ±9% for both humidity and outdoor temperature, a bypass duct opening of 6 in, and a 1/2‑in (13 mm) drain fitting. The unit operates comfortably between 34°F and 90°F and works within a 0–95% RH non‑condensing humidity window, ensuring reliable performance across most climates.

Best for: Entry‑level buyers or those on a tight budget — the Honeywell HE400A offers Coverage Area: Up to 18,000 cubic feet / 2,000–4,000 square feet

Avoid if: You lack a forced‑air furnace, duct access, or prefer a DIY installation; reliability and user satisfaction are your top concerns.

TL;DR: The Honeywell Whole Home Humidifier adds up to 17 gallons of moisture daily across 1,500‑3,000 sq ft, uses a digital humidistat with outdoor sensor, and saves up to 30 % water at a mid‑range price.

What really sets this unit apart is its moisture output—up to 17 gallons per day (64 L/day)—and a coverage envelope of 1,500 to 3,000 sq ft. The digital humidistat, paired with an outdoor sensor, automatically tweaks humidity based on weather, so you don’t have to babysit the system. At 12.5 lb (5670 g) and a compact 18.5 in depth, it fits neatly into most bypass‑duct layouts while the PerfectFLO tray keeps water distribution even.

Compared with the other four models, the Honeywell sits in the middle of the pack. It’s lighter than the premium Honeywell HM750A (18.7 lb) but a bit heavier than the HE400A (11.5 lb). Its 18.5 in depth is deeper than both the TrueEASE (10.13 in) and the HE400A (10.1 in), meaning you’ll need a bit more room in the plenum. In terms of coverage, the AprilAire 720A blankets 6,250 sq ft—far larger than Honeywell’s range—while the HE400A’s 2,000‑4,000 sq ft claim is comparable. The Honeywell also draws only 0.5 A at 24 VAC, a modest power demand versus the higher‑amp HM750A.

Users consistently praise the comfort boost and the noticeable drop in static electricity after installation. Professional reviewers note the “set it and forget it” convenience of the digital humidistat and commend the unit’s water‑saving claim of up to 30 % less water (roughly 20 gal/day). The downside that shows up in both expert and consumer feedback is the need for a professional install, a floor‑drain connection, and the fact that it operates only in the heating season.

Best for: Most users seeking a balanced, mainstream option — the Honeywell Whole Home Humidifier offers Coverage Area: 1,500 to 3,000 sq ft

Avoid if: Your home lacks a floor drain or full duct access, or you need humidification throughout the entire year