Humidifiers / Honeywell
Honeywell HCM350 Germ Free Cool Mist Humidifier (HCM350W / HCM350B)
A fifteen-year-old evaporative workhorse with UV — and no humidistat at all.
Overall score 6.8/10
Pros
- + Evaporative plus UV: no white dust, no distilled water, and a genuine (if narrowly worded) kill stage on the water
- + Tank and tray are top-rack dishwasher safe, which almost nothing else in this category can say
- + 2 gal/day rated output is real humidification, not a desktop trickle
- + Three-year warranty and a filter supply chain that has existed for fifteen years — parts are trivially available
Cons
- − No humidistat, no auto mode and no auto shut-off — it runs until you stop it, and the FiltersFast listing states the omission outright
- − The 2 gal/day output and the 24-hour runtime cannot both be true at once: the 1.1 gal tank means hitting rated output requires two fills a day
- − Two stacked consumables — a $23-33 three-pack of wicks every 30-60 days plus a 30-day Protec cartridge
- − Honeywell publishes no square footage and no decibel rating; retailers fill the gap with a 500-800 ft² figure Honeywell does not make
- − Honeywell's own store now marks the HCM350 discontinued and points buyers at the HEV320W, even though the model is still stocked and supported elsewhere
Honeywell HCM350 Germ Free Cool Mist Humidifier (HCM350W / HCM350B) review: what the specs say
A fifteen-year-old evaporative workhorse with UV — and no humidistat at all. At $89.95, Honeywell's 2009 model sits in the middle of the range — the humidifiers we compare run from $19.79 to $299.99. It scores 6.8/10 overall, calculated from published specifications across 8 categories rather than from a subjective impression.
Its strongest showing is Freedom From White Dust at 9.5/10 — the thing marketing never mentions. Ultrasonic humidifiers aerosolise whatever is dissolved in the water and deposit it as white dust on furniture — the EPA notes they are 'very efficient at dispersing minerals in tap water into the air', along with microorganisms from the tank. Evaporative and boiled-steam units do not do this at all. A high score means the technology cannot produce dust; a low score means you are buying distilled water for the life of the machine.. The weakest is Humidity Control at 3.0/10, which is the trade-off to weigh before buying: if that is the specification you care about most, one of the alternatives below will serve you better.
Worth knowing before you buy: no humidistat, no auto mode and no auto shut-off — it runs until you stop it, and the FiltersFast listing states the omission outright; and the 2 gal/day output and the 24-hour runtime cannot both be true at once: the 1.1 gal tank means hitting rated output requires two fills a day. Every specification on this page comes from Honeywell's own documentation or a verified retail listing — where a figure is not published, the table says so rather than estimating it.
Specifications and price last verified . Report an error
Full Specifications
| Humidification Technology | Evaporative wick with a UV chamber in the water tray — a fan pulls air through the wet HAC-504AW filter |
| White Dust & Mineral Aerosol | None. The mineral load stays in the wick, which is why Honeywell's manual explains that brown or rust-coloured "mineral deposit" staining on the filter is normal and does not affect performance. Tap water is fine |
| Tank Capacity | 1.1 gal / 4.2 L |
| Rated Output per Day | "2 US gallons (7.6 liters) output per day" per Honeywell's own manual — which is nearly twice the tank. Meeting the rated output means filling the 1.1 gal tank roughly twice a day, not once |
| Quoted Runtime (and at which setting) | "Up to 24 hours" — on the LOW of three settings. That is 1.1 gal in 24 h, which is barely half the rated 2 gal/day output; the two headline numbers describe two different settings |
| Rated Room Coverage | Sources conflict: Honeywell's own product page says only "medium room" with no square footage, while FiltersFast's listing for the same model states 500-800 ft² |
| Humidistat | None. Three fixed output speeds on a mechanical dial, no humidity sensor, no auto mode and no auto shut-off when the tank runs dry — you are the humidistat |
| Noise | Not published as a decibel figure by Honeywell; the product page says only "quiet operation". It is a 60W fan drawing air through a wet wick, so the top speed is clearly audible |
| Filters & Cartridges (Annual Cost) | Two separate consumables. The HAC-504 "Filter A" wick is $32.95 for a Honeywell 3-pack (a compatible FiltersFast 3-pack is $22.99) and Honeywell says replace it every 30-60 days. On top of that the Protec antimicrobial cartridge is a 30-day item. A full heating season is realistically $40-70 |
| Cleaning Burden & Dishwasher-Safe Parts | Among the best here. The tank and tray go on the dishwasher's top rack, the tank opening takes a hand, and the manual's disinfection routine is one teaspoon of bleach per gallon. Honeywell says only that it "requires regular cleaning" without naming an interval; the EPA says every third day |
| UV / Antimicrobial Claim | Two claims, both qualified. The UV chamber is rated "Up to 99.9% Germ Free*", where the asterisk in Honeywell's own manual ties it to independent testing of microbial reduction after two hours of UV exposure — a water-tray claim, not an air claim. The wick itself is separately treated as a Protec antimicrobial filter |
| Mist Temperature & Burn Risk | Cool, invisible vapour at room temperature — no burn risk at all, which is why this is the standard nursery recommendation |
| Connectivity | No wireless connectivity — three-position mechanical rotary control only |
| Material | Plastic housing; Honeywell's manual states the water tank and water tray are top-rack dishwasher safe below 158°F on a light or normal cycle |
| Warranty | 36 months |
Compare Honeywell HCM350 Germ Free Cool Mist Humidifier (HCM350W / HCM350B) With
Cheaper Alternative
Levoit Classic 300S (Classic300S) — $79.99
Premium Alternative
Canopy Bedside Humidifier 2.0 — $159.00