Blueair 203 Slim HepaSilent Air Purifier Review 2019

Last Updated: July 1, 2019

Our team tested the Blueair 203 Slim HepaSilent air purifier, so you don’t have to. Check out our full review if you think that this remarkable air purifier could be the one for you.

by AC Rated

One of the youngest of the companies we have reviewed at Air Conditioners Rated, Blueair can proudly boast a relatively short history of introducing outstanding products to the market. Our team of experts got their hands on the Blueair 203 Slim HepaSilent air purifier, assessing it under a range of criteria such as convenience, design, cleaning capabilities, efficiency, and more. Read on to see what we found.


Blueair 203 Slim HepaSilentCheck Price >


Blueair 203 Slim HepaSilent Air Purifier

Retailing for around $329, the Blueair 203 Slim HepaSilent is by no means a cheap unit. In fact, compared to some other units on the market, this unit’s price-tag is quite steep. This peaked our interest at Air Conditioners Rated, and we just had to get our hands on one to see what all the fuss was about. Well, suffice to say, we found this unit to certainly be worth the asking price. Read on below to see why.


Cleaning Capabilities

Servicing an estimated approximate area of up to 225 square feet, the Blueair 203 Slim HepaSilent air purifier is capable of 5 complete air exchanges an hour. What this essentially means is that all of the air in the room will pass through this device five times in an hour, which we would consider to be a very efficient rate of air exchange. With moderate Clean Air Delivery Rates (CADR), this unit sits comfortably in the middle of the market. Due to the high frequency of energy exchanges, we would recommend this unit for people suffering from allergies.

The Blueair 203 Slim HepaSilent air purifier benefits from an exceptionally well-designed air filtration process, starting with a carbon pre-filter which is engineered to combat odours, and is where large particles are trapped. Then, the air is passed through an electrostatic HEPA-type filter, which will trap the smallest of particles.

Finally, the air is passed through an ionizer, which will release negative ions along with the air, which will charge airborne particulates. The purpose of this is so that on the next pass through the device, these charged particulates will cling to the electrostatic filter. This system allows the Blueair 203 Slim HepaSilent to capture particulates down to 0.01 microns at 99.97% filtration efficiency.

Note: The ionizer on this device cannot be switched off. This feature is sometimes demanded of the manufacturer, as ionizers have been shown to release trace amounts of ozone into the air. Ozone has been shown to cause certain lung diseases. However, purifier unit ionizers will usually only release a very small, insignificant amount. While this unit has been tested and certified by CARB for ozone emissions, we recommend that users suffering from respiratory issues seek a unit that does not have an ionizer regardless.

See below for this units CADR specifics across a range of criteria:

  • Smoke: 155
  • Dust: 155
  • Pollen: 155


Efficiency / Certifications

Coming Energy Star certified, this unit adheres to a strict set of regulations regarding energy consumption, set out by the Environmental Protection Agency. This means that the Blueair 203 Slim HepaSilent will cost you less to run than many other units on the market. Efficient operation is further encouraged with the inclusion of three speed control options on the device, allowing the user to get the performance they need from their unit, no more, no less.

The Blueair 203 Slim HepaSilent also comes AHAM certified, meaning that the CADR figures supplied by the manufacturer are in fact, accurate. Additionally, this unit has been certified by the California Air Resources Board (CARB) for ozone emissions.

Unfortunately, there was no information available concerning this product, relating to any other certifications at the time of this review.



A unique feature that we have not come across in any other units on the market, the Blueair 203 Slim HepaSilent comes with a magnetic timer that alerts you when it is time to change the filter in your device. This is important, as a dirty filter will inhibit efficient operation. This timer may be attached to any magnetic surfaces in your home, including the unit itself, or your refrigerator for example.

The user interface, located on the side of the unit, consists of a dial, for easy selection of what extent you would like your unit to operate to, while an indicator will notify the you when it is time to change the filter.

Unfortunately, this unit lacks the convenient features that we would usually look for, such as sleep mode, auto mode, a remote control, or a 24-hour timer.



As stated above, this unit’s user interface is remarkably user friendly, and this is something that Blueair certainly should be praised for. Too often are interfaces on such devices overly confusing and cluttered. With the Blueair 203 Slim Hepasilent, there is one dial, which allows the user to alter their product’s performance.

With a sound level of 32-56dBA (depending on what setting the unit is operating on), this unit is capable of remarkably silent operation. For reference, the average human conversation would usually register at approximately 60dB, while a whisper will usually register at about 30dB.

Weighing 24lbs, this unit is surprisingly heavy for an air purifier, however this is still a manageable weight. Unfortunately, the Blueair 203 Slim Hepasilent does not come supported by caster wheels, meaning that the device will have to be lifted in order to transport it from one room to the next.

Aesthetically, this unit has won awards for its minimalist and modern design, combining aesthetic appeal with functionality in a union that promises efficiency, reliability, and professional performance.

Dimensions (Inches):

Height: 21″

Width: 17″

Depth: 10″


Help & Support

The Blueair 203 Slim HepaSilent air purifier comes backed by an impressive industry leading 5-year warranty. For terms and conditions we recommend contacting Blueair directly.

In addition to this, an in-depth FAQs section is available on the company website, alongside downloadable user manuals which are useful in the case of you losing your physical copy. Also on the Blueair website are video tutorials, quick guides, and a store locator.

Representatives are contactable via email, telephone, or through one of their various social media presences.



In conclusion, our team has unanimously agreed that this is a very effective unit. For its size, the Blueair 203 Slim HepaSilent performs exceptionally well. Its well thought out filtration system removes virtually all pollutants from the air, while the unit provides up to 5 air exchanges an hour in a small room. We do, however, take issue with the lack of several convenience-enhancing features that we would usually expect from a unit of this price. That being said, the absence of such features can be forgiven due to this unit’s sheer effectiveness in purifying the air of a room.