Alen A375 Air Purifier Review by Garth Wernsman
|Last Updated: 18/12/2018 12:53 UTC. Because of the rate with which conditions change, prices may slightly vary or product may be temporarily out of stock when checking out the product at the vendor's site. Any price and availability information displayed on the vendor's site at the time of purchase will apply to the purchase of this product.|
Alen air purifiers have a reputation for high filtration efficiency. That’s well demonstrated even in the relatively modest model, the Alen A375.
Basic Design & Specs
Curiously, the Alen A375 name seems not logical. The Alen A350 covers up to 750 square feet and products usually increase the spec as the product number increases. Yet, the A375 only covers up to 650 square feet. That’s backwards from the usual situation.
That said, there’s nothing funky about the spec here. Many air purifier models state a coverage figure and you have to hope it lives up to it. Alen has a well-earned reputation for understating their ratings. The A375 will definitely cover that area, provided you don’t have cathedral ceilings – and sometimes even then.
The case size is exactly the same as the A350. Here, that means a chassis measuring 17.5″ high x 18.5″ wide x 8.2″ deep. And, at 19 lbs, it weighs about the same. The A350 is 16 lbs.
5-Stage Filtration System
Here, too, the Alen A375 shows its family resemblance to its cousin. The filter system is a large tri-layered unit that can be replaced easily.
It incorporates first a pre-filter that, like most, has two primary purposes. One is to do as the name suggests: filter. Human and pet hair, large dust balls or particles, and the like get trapped here. The second important function is to ease the job done by the other layers, letting them function at peak ability.
The pre-filter is both washable and can be vacuumed. However, since the filter is a 3-in-1 style system, washing it could be a bit tricky. Getting the HEPA wet would definitely undercut its function, if not ruin it entirely. Luckily, vacuuming is generally good enough for this stage.
Just behind it (from the perspective of airflow direction) is the HEPA filter. It’s neither extraordinary nor flawed. Some filters of this type are the equivalent of hospital operating room units. Not even tiny viruses get through. This one does almost the standard duty – removing 98% of particles down to 0.3 microns.
I say “almost” intentionally… One reason you so often see that last figure listed with a HEPA filter is that it’s one of the official criteria. The DOE (US Department of Energy) standard requires removal of at least 99.97% of the particles that flow through to be a True HEPA. This one clearly doesn’t qualify on that score.
Still, experience shows that it does a good job of radically reducing home air pollutants. One reason is that – in one option (see below) – it’s silver coated, and therefore has some anti-bacterial ability.
By design, a HEPA doesn’t stop chemical odors and the like. Luckily, behind the HEPA-like filter is an Activated Carbon filter. It does get out the overwhelming majority of VOCs (household cleaning product vapors, for example). It also filters pet dander (the little protein molecules, part of the skin cells pets shed, responsible for allergies). And, it does an excellent job of removing cigarette smoke, pet urine odor, and other offensive chemical compounds.
The A375 does have a feature that puts it above the A350 in one respect: UV light. Inside the filter system there’s an additional component that shines ultraviolet light onto the passing airstream. That zaps a wide array of viruses, bacteria, and other nasty things before ejecting the air out the exhaust. If you’re sensitive, that can make a big difference.
Finally an Ionizer pumps out negative ions charging particles in the air making them larger and heavier. The larger size makes them easier to trap. Due to the larger weight they tend to float more readily to the floor or carpet, where they can be vacuumed up or sucked in by the air purifier. They also attach more readily to positively charged surfaces where they stick, harmlessly waiting to be wiped off.
As with the A350, though, this 3-in-1 filter style has a downside. It certainly could not be easier to change. You pop off the front panel, pull out the large rectangle, then pop in a new one. But it means you have to replace them all at the same time. Depending on the nature of your home environment, that may be forcing you to change, say, the Activated Carbon filter long before the HEPA is worn out. Or vice versa.
The implication of that is that you might have to spend more money for operating costs per year than necessary. It’s a tradeoff between simplicity and annual running expense, and only you can decide whether it’s worth it. At roughly $60-$90 per filter (the same for the A350), it’s a coin toss in my mind.
There are actually several filter options from which to choose. The base level – the HEPA-Fresh Filter (BF25A), as Alen calls it – is $59 (currently). It’s the plain vanilla of the bunch, but even in this elementary style it does a fine job.
The next step up is the HEPA-Silver Filter (BF25A-Silver). It sells for $69 and has the ion coating that kills bacteria, described above. It’s also great at removing mold, cigarette odors, and similar allergens.
The most expensive version is the HEPA-Odor Cell Filter (BF25A-MP), costing a hefty $89. It’s designed for getting every last spec of odor out of your home generated by cleaning products, smoke, and more. It does a superb job of that but, if replaced according to the company’s (quite reasonable) schedule of once every six months, the annual operating cost becomes pretty substantial.
Sensors, Controls, and Display
One reason the A375 can be as effective as it is, despite the relatively elementary filter system, is the sensor system. It monitors the air stream and detects pollutant levels. When that rises, the unit automatically increases the fan speed until the offending material is reduced below detectable level. If you want a practical demonstration, just light a cigarette in front of the air purifier. You’ll hear the higher speed kick in.
There’s a filter-change indicator light that works in conjunction with that system to alert you to the need. The display also provides easy-to-read indicators for fan speed, timer, and amount of dust and smell.
All the buttons provide positive feedback so there’s no need to wonder if they’ve been pressed, even if you’re having difficulty reading the panel. Hey, I don’t always have my glasses handy, either!
The controls follow a similar theme, being ultra-easy to use. The on/off switch is right up front near the top. Just above that is the fan speed control, timer and ionizer (de)activate button and indicator. Also, since the A375 has a UV light, there’s an additional UV Light (de)activate button and an indicator to show whether it’s on or off.
The Alen A375 is currently selling for the same price as the A350 which covers a larger area. However, this model has with the UV light an extra filtration stage which will be a big value to some buyers and also comes with a remote. Either way you go, you’ll be getting a fine air purifier.