Vornado Evap40 review

Almost every humidifier in this category claims a room size its own published figures cannot support. We check every one against its own arithmetic, and the Evap40 is the only portable that comes out the other side with room to spare.

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Vornado Evap40 review - ranked, with the arithmetic

#	Product	Best for	Gal/day	Price
1	Vornado Evap40Top pickVornado publishes an output figure and a coverage figure, and the two agree. Four gallons a day covers about 1,180 sq ft at our derived rate against a 1,000 sq ft claim.	The only coverage claim here the arithmetic supports	4.0published · 1,184 sq ft	$149.99 - Amazon#ad
2	Levoit Superior 6000SSix gallons, evaporative, and a Dry Mode that dries the wicks between runs. The 3,000 sq ft claim needs five times the output its own run time implies.	Mist-free humidification with a drying cycle	2.0implied · 592 sq ft	$249.99 - Amazon#ad
3	Honeywell HCM350 Germ Free Cool MoistureA break-resistant, dishwasher-safe tank and a wide opening. It is the only unit here designed so the hardest part of ownership is easy.	Cleaning, without qualification	1.0implied · 296 sq ft	$76.42 - Amazon#ad

The claim, and the check

Vornado publishes up to 4 gallons of water output in 24 hours when operated continuously on high, for spaces up to 1,000 square feet.

That is the opposite of the pattern everywhere else on this site, where claims routinely exceed implied output by two to five times. It is the single strongest reason to buy this machine, and it is a reason you can verify before paying.

The humidistat, which matters more than it reads

Vornado states automatic humidity control with a built-in humidistat. On a machine of this output that is not a convenience feature, it is a safety rail: 4 gallons a day into a room that only needs two will push past the EPA's 30 to 50 percent band and put water on the coldest window in the house.

It is also evaporative, which means it is partly self-limiting anyway - evaporation slows as the air approaches saturation - and that the minerals in your tap water stay in the wicks rather than landing on the furniture as white dust. For a machine sized at a whole floor, that second point is worth as much as the first.

The five-year cover

Vornado publishes a 5-Year Satisfaction Guarantee. That is the longest cover any maker in our set publishes - more than double Levoit's two-year limited warranty, and two years beyond Honeywell's three on its warm-mist model.

A warranty is not a lifespan and we will not pretend otherwise; nobody in this category publishes failure rates, including us. But it is the only durability statement a manufacturer puts in writing, and a company willing to stand behind a machine for five years is telling you something a product photograph cannot. How long humidifiers last sets out what else can honestly be said.

The two figures Vornado will not publish

For a machine this well documented on the number that matters most, the omissions are strange.

• No wattage. So the seasonal electricity cost of a machine you will run continuously from November to March cannot be computed before purchase. For comparison, we can compute it for every Levoit in our set.
• No run time. So the refill interval cannot be worked out either. A 4-gallon tank at 4 gallons a day is roughly daily on continuous high, but Vornado does not say that and the figure changes with the speed.
• No decibel figure. It is an evaporative unit, so it has a fan, and fan noise rises with output. In a bedroom that absence matters; in a living room much less.
• No wick replacement interval. Two wicks are included and Vornado does not say how often they are replaced, which means the running cost has a hole in it. That is common - four of the filtered units we cover publish no interval.

Who should buy it

• Anyone humidifying an open living area of up to roughly 1,000 square feet who wants a claim that survives checking. This is the machine's core case and it is a strong one.
• Hard-water households. Evaporative means the minerals end up in a wick rather than on the furniture.
• Anyone who wants the machine to stop on its own, which the built-in humidistat and the self-limiting mechanism both contribute to.
• Anyone buying for static or whole-floor dryness, where bedroom-scale machines fail - our static electricity picks lead with it for that reason.

Who should not

• Bedroom buyers who need a published noise figure. It has a fan and Vornado publishes nothing about it. The ultrasonic units publish decibels with the setting attached; this does not.
• Anyone who needs to budget the running cost exactly. Without a wattage or a wick interval, two of the four cost components cannot be computed.
• Anyone needing more than about 4 gallons a day. That is the top of the portable market, and above it the honest answer is a ducted unit - see 2,000 sq ft.

The verdict

It is the most trustworthy coverage claim in the portable market and the longest guarantee we have found, in a machine that is deliberately plain about everything else. If you want a humidifier that will hold a floor and you would rather have one checkable number than a page of unverifiable ones, this is the one to buy. If you want to know what it costs to run before you buy it, Vornado has not told you - and that is a fair thing to hold against it.

The wicks, which are the running cost

Two wicks are included and they are the only consumable. Vornado does not publish a replacement interval for them, which means the running cost of this machine cannot be computed in advance - the same gap four of the filtered units we cover leave.

What to do about it in practice: replace on the functional signals rather than a schedule. A wick that has gone stiff, crusted or discolored has stopped being a wick, and the symptom is a drop in output at the same fan speed with no other explanation. That is the same guidance we give for the Honeywell, and for the same reason - filter replacement covers the arithmetic when a maker does publish an interval and what to do when it does not.

The related point is that an evaporative machine's wick is the mechanism, not an accessory. A neglected one does not make the humidifier noisy or leaky; it makes it quietly ineffective, which is far harder to notice and is the most common reason an evaporative unit gets replaced when it did not need to be.

Against the ducted alternative

At 4 gallons a day this is the top of the portable market, and it is worth knowing where that sits against the other end. The Aprilaire 700 publishes 18 gallons a day and has no reservoir at all. If your requirement is above about 4 gallons a day - roughly a 1,200 square foot open floor - then no number of Evap40s is the elegant answer, and whole house versus room is the decision to read instead.