Photo of Winix Signature and Ultimate Pet SeriesIn this article, we’ll be reviewing two Winix air purifier series that share a lot in common:

  • Signature Series
  • Ultimate Pet Series

Both of these series provide an advanced level of air purification, but the difference between each can be hard to spot. We’ll explain what these differences are in the reviews below.

What you may not know, and is not clearly explained on the Winix website, is that the Ultimate Pet Series is the flagship product line out of the two series.

The Signature Series is the updated version with new models that contain minimal feature enhancements.

Keep reading below to find out what the similarities and differences are between the Signature and Ultimate Pet Series.

Note: The Ultimate Pet Series product line was created in response to the rising number of people that have developed pet allergies. This series has been the #1 best seller for homeowners that want to get rid of pet dander and other allergens that cause health problems. No other product on the market has been designed to combat this specific problem as well as the Winix Ultimate Pet Series, except for the new Signature Series. We have recommended the WAC9500 in another article: Best Air Purifiers for Pet Odor.

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Winix Signature and Ultimate Pet Series Review

Similarities between Both Series

Photo of Both Air Purifier SeriesAll models within the Signature and Ultimate Pet Series include:

  • A 5-stage air filtration process that uses:
    • Antibacterial pre-filter (washable)
    • True HEPA filter (captures 99.97% of dust, allergens, pet dander, mold spores, etc.)
    • CleanCel treatment (neutralizes bacteria and viruses on contact)
    • Advanced Odor Control Carbon filter (washable)
    • PlasmaWave technology (see below for how this works)
  • Air quality and light sensors
  • Automatic hands-free operation mode
  • 4 fan speeds
  • Filter change indicator
  • Sleep mode
  • Digital display panel
  • PlasmaWave on/off switch
  • Remote control
  • Energy Star qualified

Differences between Each Series

As you just saw in the list above, the Signature and Ultimate Pet Series contain a lot of the same functions and features. So, now the obvious question is, “How has Winix made them different?”

The key difference between the two series, and within each product line themselves, is the maximum room size each of these air purifiers can handle.

The only other distinction is the exterior design and color of the products.

Here’s how each model compares in regards to area coverage:

  • WAC9300 = 218 sq. ft.
  • WAC9500 = 283 sq. ft.
  • U300 = 300 sq. ft.
  • U450 = 450 sq. ft.

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How PlasmaWave Technology Works

The patented Winix PlasmaWave technology works by eliminating airborne pollutants through the use of water vapor. This unique process allows it to create cleaner, fresher air without producing harmful ozone byproducts. This revolutionary technology is excellent at removing viruses, bacteria, chemical vapors, odors and gases.

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Throughout this article, we’ve shown you how the Signature and Ultimate Pet Series are practically identical in every way except for the external casing design and maximum room size coverage.

If you’re still trying to decide on which model and/or series to get, here are some final things to consider before making a purchase:

  • There’s minimal difference in area coverage between the Ultimate Pet Series WAC9300 and WAC9500 (only 65 sq. ft.) The best investment would be to get the WAC9500 air purifier.
  • The difference in area coverage between the Signature Series U300 and U450 is significant (150 sq. ft.) The size of the room you want to purify should determine which is the better air purifier to get.
  • The room area coverage between the lowest models in both series, U300 and WAC9300, is 82 sq. ft., yet the price separation is roughly $100. If you’re looking to use an air purifier in a small to medium sized room and  don’t mind the older silver design, you can save a substantial amount of money getting the WAC9300 air purifier.
  • The difference in room area coverage between the highest models in both series, U450 and WAC9500,  is 167 sq. ft. and the price separation is around $100. If you can afford it, the U450 is the better investment because the maximum output is so substantial.

More Reviews Worth Checking Out

Compare the Winix FresHome and PlasmaWave Series
Compare Air Purifiers by Other Manufacturers
Guide on the Best Rated Air Purifiers

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