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The Honeywell AirGenius 4 HDF310 is not quite as simple as it looks. But what is it hiding? Does it produce ozone? Is it too small for the area it promises to clean? Are the filters washable? Who does it suit and how does it compare to other models?

Take a deep breath and dive into air purifier thrill, (don’t be embarrassed, you know it’s exciting).

====>> In a rush? Click here to see the current price for a Honeywell Airgenius 4 HDF310 on Amazon

What Interesting about the Honeywell Airgenius 4?

Where do I start? There are a couple of key things which interested me the most when researching this Honeywell number.

Honeywell HFD280B Compact AirGenius 4 Air Cleaner/Odor Reducer,Black

Firstly, the issue of the ionizer. Further down I’ll go deeper into this issue, but here’s the gist: it does have an electronic ionizer as part of its cleaning function. It seems that you wouldn’t know this unless you pored over the manual, as it’s not recorded anywhere else.

Secondly, the filtration. The main filter is the patented ifD filter, which is washable and permanent. Yup, no replacements or extra costs. You simply maintain it with a gentle wash every few months. However, it’s not classified as HEPA, which seems disappointing. On further research, the filter does capture 99.9% of particles as small as 0.3 which is the threshold for HEPA filtration. For that reason, you don’t need to worry that allergens won’t be caught, they will.

This purifier comes with two pre-filter options: a washable mesh pre-filter and an odor-reducing pre-filter. You can choose either or, and swap them around as you see fit. The odor-reducing pre-filter needs to be replaced and cannot be washed.

Does it reduce dust and mold?

Even though a few people have seen no difference in household dust, a number of others have seen a great improvement. I think it depends on what size room you place this purifier in. It seems that it does very well in small (or very small) rooms, but the effectiveness wanes in medium-to-larger rooms.

Now for the mold. Horrible, musty mold. To really get rid of the stuff, it has to be treated at the source. Visible mold must be killed and wiped away, and damp rooms need to be dehumidified. However, mold spores can be captured by air purifiers, along with all the other nasties floating along with them. Mold spores are as small as 3 microns, which is no sweat for an air purifier like this one to tackle.

In less words, yes, this model can capture airborne mold spores.

Does it remove tobacco, pet or diaper odor?

This model is called an “air purifier/odor reducer”, which refers to the option of the odor-reducing pre-filter. You have an option of using the general pre-filter or the odor-reducing. To me, it seems strange not to just use the odor-reducing filter to get that extra freshness.

Judging from the experience of others, this air purifier does reduce, and in some cases, remove odors, depending on how strong the smells are. There are plenty of positive reviews raving about fresh air, clean rooms and disappearing odors.

Does it produce ozone?

Curiously, there is no mention of an ionizer anywhere apart from the official Honeywell AirGenius 4 HDF310 manual. While perusing the manual, I came across the “how your air cleaner works” section. All in order, except stage 3 which is described as “electronic ionizer”.

The level of ozone production is still a mystery, as there’s very little information about the ionizing process used in this machine. However, since it has an ionizer, we should assume that at least some ozone is produced.

What do other customers and reviews say?

Right, time for the review analysis. Here we breakdown of the happy, the angry, the delighted and the confused comments which have been awarded a rating from 1 to 5 stars.

The Honeywell AirGenius 4 HDF310 has an okay “star ratio”: 67% are in the 4 to 5-star section, with 26% in the 1 to 2-star section. Not too shabby. But what’s important is why people have given these ratings.

Here are the most common (or the most mention-worthy) comments in the positive and negative camps:


Higher settings are too loud: you can count on this complaint across the board of air purifiers. There’s always someone who finds the noise too loud, while others swear they can barely hear it. With this model, the “too loud” complaints are directed mostly at the two highest levels, “allergen” and “max”. This makes sense since these functions are for super-sized cleaning rather than general, everyday cleaning. The lower two levels, “general” and “sleep” are fine for most people, but there are still some comments claiming that even those levels are too loud.

Too small: some people have been unpleasantly surprised about the size of this model. They’ve found that the amount of air being moved doesn’t seem sufficient for the room they’ve chosen to place the purifier in. A few reviewers have suggested that this model is best for small bedrooms or offices with less air to circulate. The size of the machine has also been named as a culprit for the noise level, with suggestions that it’s best to just go for a larger model in the same range.

Plastic smell: contradictory to the positive reviews regarding odor-reducing abilities, some people have said that the machine emits a plastic-like smell. Fortunately, it seems that this is just a “settling in” habit of this air purifier when it’s first installed, as it will eventually go away.


Effectively reduces odours: happy reviewers have commented that smells have been noticeably reduced, leaving fresh, clean air behind. Microwaved food smells, mustiness and pet odors have been specifically named. You’ll just have to get over the plastic smell for a little while when you first plug this model in.

Love the washable, permanent filters: the filters are a huge favorite among reviewers, and they’ve been specifically named as the best aspect of this air purifier. The cost-effectiveness and ease of use gets two thumbs up from consumers.

Reduces sinus and breathing-related issues: this is a great comment to see among the reviews. Allergies, blocked sinuses and breathing issues (i.e. asthma) can put a giant damper on daily home-life. Many people have said that since using this air purifier, their allergy-related health issues have really improved.

Reduces dust: there are a few notable reviews which mention the reduction in dust since using this purifier. Some people have also said that since they’ve never had much of a dust problem they can’t be sure how effective it is, but they have noticed a fresher, cleaner feel in their home. I take this as meaning that yup, the dust has been reduced.

What are the technical specifications?


Recommended room area 250 square feet
Clean air delivery rate Tobacco smoke – 161, Dust – 16, Pollen – 170
Special features/settings

The control panel is neatly located on top of the air purifier and it’s pretty simply to figure out. However, there’s always something to confuse me, even on the easiest of machines. For anyone who needs more explanation than a button and a symbol (or has lost their manual), here’s a little helper on what each button does and how to use it:

Timer button: the button with the clock symbol is used to set the auto-off timer. This just means that the purifier will run for a certain amount of time before switching off. There is a 2, 4 and 8-hour option with a little blue light to signify which one has been chosen.

Accent light button: next up is the button with the lightbulb symbol and lights labelled “high” and “low”. This button is to control the accent light at the base of the machine. It’s really there for aesthetics, or potentially to illuminate a dark hallway or room for nighttime guidance. You do have the choice to turn it off completely.

Purification level button: the button with the little leaf symbol controls which setting you have the machine on. The levels are laid out as 1-sleep, 2-general, 3-allergen and 4-max. Press the leaf button until your desired level is illuminated.

Oscillation button: the oscillation button is the one with the arrows pointing in opposite directions. Turn this on if you want the fans to move from side to side (oscillate). The purpose of this is to (apparently) give the air flow in the room a bit of a booster for a more effective clean.

Filter check/reset button:  the little light labelled “check filters” is exactly that; it lights up when it’s time to check the filters. Below this light is the “ok” button. Once the filters have been cleaned or replaced, hold down the “ok” button and the light will turn off until the next time the filters need to be checked.

Filter type Permanent washable ifD filter (more details on this further on), choice of either a washable pre-filter or an odor-reducing pre-filter.
Energy usage impressively, it has earned itself the Energy Star for energy efficiency
Colour Black
Noise level Level 3 and 4, (“max” and “allergen”) are loud, but levels 1 and 2 and nice and quiet. The question of noise is explored further below

Dimensions & Weight 

Size 12.17 x 12.24 x 29.88 inches
Weight 8.05 pounds

How do you use it?

Apart from checking, cleaning and replacing filters, this air purifier takes care of itself. Here’s a quick checklist of how to get it set up:

  • Make sure there’s no plastic wrapped around the filters and slot them into place in the unit
  • Find a flat, even surface with a power outlet handy
  • Make sure all sides of the air purifier are clear of objects (at least 3 feet)
  • Plug in, turn on and choose your desired setting
  • Have a play around with the accent light to see if it’s to your taste or if you’d prefer it to stay off
  • Enjoy the fresh air
  • Keep an eye on the filter light or simply mark 3 months on your calendar for a filter check
  • Wash the ifD filter and the regular pre-filter, dry them out, put them back
  • Replace the odor-reducing filter if using

That’s about the extent of it.

How do you clean it? Is it easy to clean?

Absolutely, it is very easy to clean. To get the external unit dust-free and shiny, just wipe it down with a damp cloth.

The filters are easy to clean and there are a couple of ways to do this.

For the main filter, (the ifD permanent filter) you can simply give it a wash with water, let it dry completely then pop it back into the machine. Or, if it needs a little extra TLC to get all the gunk out, you can soak it for a few minutes in warm, soapy water. Rinse it out, let it dry, then throw it back into the unit. Easy.

Now for the pre-filters, they’re easy too. If you’ve chosen to use the washable pre-filter, wash it every few months (I’d just do it in one go with the ifD filter). Rinse, dry and replace. However, if you’re using the odour-reducing pre-filter (the “K” filter), you need to replace it every few months.

How Does It Compare to other models?

Next up, a quick comparison between the HFD310 and two other Honeywell models.

Honeywell Airgenius 4 (HFD310) vs Airgenius 5 (HFD320)

The AirGenius 5 is really just an upgraded version of the AirGenius 4.

The AirGenius 5 has the same CADR (161) and the same recommended room area (250 square feet). It features the same oscillation feature, accent light, energy rating and shut-off timer feature. However, it has 5 cleaning settings instead of 4 (hence the name). The AirGenius 5 has the same “sleep”, “general”, “max” and “allergen” settings, but it also has a “germ” setting which the AirGenius 4 doesn’t have.

The control panel is a little different on the 5 also, it has touch-screen buttons as opposed to the regular buttons on the 4.

I think the AirGenius 5 is a good alternative to the 4, as it offers the same features but a few extras to make it a little more versatile.

Honeywell Airgenius 4 vs Honeywell HPA300

The Honeywell HPA300 is not part of the AirGenius family, so it’s got quite a few differences. Firstly, the size and shape. The HPA300 is 20.08 x 10.83 x 22.32 inches and is much wider than the slim-line AirGenius.

The HPA300 caters to rooms as large as 460 square feet, a much larger area than the AirGenius 4. The CADR rate for the HPA300 is higher to suit the larger room size: 300 CADR for smoke, 320 CADR for dust and 300 CADR for pollen.

The HPA300 has a different filter system. It has a true HEPA filter (as opposed to the ifD filter in the AirGenius 4) and an activated carbon pre-filter.

The HPA300 doesn’t have the oscillation feature, but it does have the shut-off timer.

There are 4 cleaning settings on the HPA300, just like the AirGenius 4. However, the HPA300 has a “germ” setting but not a “sleep” setting like the AirGenius 4. The HPA300 settings are: “germ”, “turbo”, “general” and “allergen”.

What is the cost of replacement filters and where to get them?

The Honeywell website sells all of the replacement filters you’ll ever need…which really should only be the odour-reducing K pre-filter. You can order a 2-pack of these for as low as $15.95 on special or $29.95 as the regular price.

In the unlikely event that you do need to replace your washable pre-filter or your ifD permanent filter (perhaps you lose them, forget to dry them properly…spill wine on them), call Honeywell directly. It seems there are no replacement filters of these types available to buy online.

How often do filters need to be changed and can’t they just be cleaned?

If you can’t bear the thought of non-washable filters which must be replaced, you’re in luck. The main filter (the ifD) is permanent (i.e. no replacing needed). It must be washed once every 3 months. The washable pre-filter is washable (obviously), and is also permanent. However, the odour-reducing K filter must be replaced as opposed to washed.

So, here’s the rundown:

  • Main ifD filter = permanent, washable, no replacing
  • Regular pre-filter = washable, permanent, no replacing
  • Odour-reducing K pre-filter = needs to be replaced, not washed

Are there other replacement parts, where do I buy them?

You should only have to replace the filters, as there are no other parts readily available. If you do have trouble with the grilles or control panels, use your warranty to get them replaced or fixed. I don’t think there’s much risk of this happening unless you get a total dud.

How loud is it?

Well, it depends on which setting you’re dealing with. The two highest settings (3: allergen and 4: max) are said to be rather loud, too loud for some. But, they are generally to be used for shorter bouts of cleaning, not as a 24/7, everyday mode. Level 1 (sleep) is very quiet as you’d expect, and level 2 (general) is gently audible and has been described as gentle “white noise”.

The “oscillate” setting seems to be bugging a few people with increased noise as the fan moves from side to side.

Interestingly, a few people have commented that because the unit is so small, the noise level increases. A few have said it would be better to buy a larger unit so there’s less chance of hearing the mechanisms work.

The takeaway?

Judging by the reviews, the two highest settings can be described as “loud” by air purifier standards. However, the lowest two settings are definitely quiet enough for someone who can bear a tiny bit of background noise.

What’s the warranty?

Honeywell provides a 5-year warranty.

Can I find it at other retailers like Walmart, Home Depot, Kmart or Target?

  • Walmart stocks the AirGenius 4 HFD310.
  • Home Depot doesn’t stock the AirGenius 4 HFD310 as of now, but they do stock the AirGenius 5.
  • Target doesn’t stock the HFD310 model. However, they do stock the HFD280B which is basically the same, but caters to a smaller room size (150 square feet).

What’s The Best Price For The Honeywell Airgenius 4 and where can I buy it?

The best deal for the Honeywell AirGenius 4 HDF310 is usually with Amazon, but Walmart is runner up. Still, prices change very often, it’s a good idea to check their listing on any given day.

Verdict: Is This air purifier For You?

This could be for you, if you can say yes to these conditions:

  • You need an air purifier for a small room
  • You’d like the option of an odor-reducing filter
  • You are concerned about energy efficiency and prefer an Energy Star qualified machine
  • You’re not bothered by a little bit of noise during more intense purifying sessions
  • You’d really love a washable, permanent filter
  • You’d like to reduce allergy symptoms and breathe easier
  • You’re not bothered by an ionizer and potential ozone production

However, if you’ve got a larger room to deal with, you can’t abide by an ionizer and you have to have total quiet, keep searching.

Click Here to See the Honeywell Airgenius 4 (HDF310) on Amazon

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