Blueair 511i Max Air Purifier – Tested and Reviewed!

Full Review

We have tested a few air purifiers from Blueair’s Blue Pure series, but since the company frequently updates the lineup with new or improved models, keeping up with and testing each release can be quite challenging.

Last year, I reviewed the Blueair Mini Max, which is actually the smallest air purifier in Blueair’s lineup.

This time, I’m testing a slightly larger model, the Blueair 511i Max. What caught my attention about this minimalist air purifier is its smart app connectivity, which unlocks a range of advanced features while maintaining a simple, minimalistic design and easy-to-use controls.

I believe this review will be especially interesting for Blueair enthusiasts, as well as for those who haven’t had the chance to try a Blueair air purifier yet.

How We Tested the Blueair 511i Max?

1. For the filter efficiency testing, we used the Temtop LKC-1000S laser particle meter, which measures PM2.5 (µg/m3), PM10 (µg/m3), Particles (per/L), and HCHO (mg/m3) in the air, and also calculates the AQI.

2. We placed the Blueair 511i Max in two separate performance tests, one in a 194 sq. ft. (18 m²) room and the other in a 320 sq. ft. (30 m²) room. Then, we recorded the initial air quality values using the Temtop laser particle meter and let the Blueair 511i Max run at maximum speed.

3. After 60 minutes, we measured the new values using the Temtop laser particle meter and saved the data.

4. Next, we placed the Blueair 511i Max in a glass box, which we then filled with smoke. Then, we measured how much time was needed for the air purifier to remove all the smoke from the box.

5. Using a special noise measurement tool, we tested the air purifier’s noise level at all speeds. We measured the noise level on the dBA scale.

6. Finally, we measured the power usage at all speeds using an energy meter, after which we calculated how much it would cost to use the device at a particular fan speed for one month. For reference, we used an energy price of $0.12 per kWh.

Let me first say a few words about this air purifier’s room coverage.

The Blueair 511i Max has a CADR of 152 CFM (258 m³/h), making it most suitable for rooms up to 236 sq. ft. (22 m²). This coverage is confirmed by its Energy Star certification. It will clean the air 4.8 times per hour in the recommended room size.

Based on its specified coverage, we tested it in two different rooms, one slightly smaller than the recommended size and another that was larger.

In addition to our standard testing procedure, I also used it in my own place for a while. What I noticed is that while the Blueair 511i Max effectively removes airborne particles, it isn’t the best choice for homes with pets.

Additionally, it struggles with neutralizing strong odors, such as cooking smells.

Testing in a 194 sq. ft. (18 m²) Room

In the first test, we placed the Blueair 511i Max in a 194 sq. ft. (18 m²) room.

After running at maximum speed for 60 minutes, it successfully reduced PM2.5 particulate matter from 104.8 to 8.3 µg/m³, resulting in a 92% improvement in air quality.

Compared to similar air purifiers in its class, this is a solid result. For instance, the Levoit Core 300S achieved a 94% improvement under the same conditions.

Overall, I would say the Blueair 511i Max delivered outstanding performance in this test.

Testing in a 320 sq. ft. (30 m²) Room

In the second test, we placed the Blueair 511i Max in a 320 sq. ft. (30 m²) room and let it run at maximum speed for 60 minutes.

By the end of the test, it had improved air quality by an impressive 90%.

This was an excellent result, especially considering that the room size exceeded the recommended coverage for the Blueair 511i Max.

The Blueair 511i Max offers four fan speeds, including night mode (sleep mode).

We measured its noise levels at all speeds using a specialized noise measurement tool. At the lowest speed, it produces a sound of 40.1 dBA, while at maximum speed, it reaches 61.6 dBA.

This is a solid result, especially considering its CADR.

As shown in the provided chart, the Blueair 511i Max ranks among the quietest air purifiers at the lowest speeds.

For comparison, the Winix 5510 produces 65.7 dBA at maximum speed, while the AEG AX5, which has a similar CADR to the Blueair 511i Max, operates at 56.8 dBA.

Overall, I would say the Blueair 511i Max is well-optimized for noise levels.

Blueair’s Blue Pure series is well known for its highly energy-efficient air purifiers, and the Blueair 511i Max is no exception.

This model features a well-optimized 20W motor, making it one of the most energy-efficient devices in its class.

At maximum speed, the Blueair 511i Max consumes approximately 17.8W. This means that if you were to run it 24 hours a day at maximum speed for an entire month, your electricity bill would increase by only $1.56.

This is an extremely low power consumption cost and is comparable to some of the most energy-efficient air purifiers we’ve tested.

For example, the Blueair 411 Auto would cost about $0.80 under the same conditions, while the Shark NeverChange HP152 would cost approximately $2.24.

In addition to electricity costs, there is also the cost of replacement filters, which typically last up to 9 months.

Considering that replacement filters are very affordable and that the device runs on a motor of just 20W, it’s easy to conclude that the Blueair 511i Max is highly cost-effective to maintain annually.

Filtration Technology

The Blueair 511i Max uses four-stage filtration technology consisting of a pre-filter, particle filter, activated carbon filter, and ionizer.

The main filter is built from two layers: a particle filter and a carbon filter, while the pre-filter is a separate layer.

By default, the Blueair 511i Max comes with the original filter, but you can also buy the Smoke Stop filter, which provides enhanced odor neutralization, or the Allergy Stop filter, which is more effective at capturing allergens from the air.

Although it doesn’t use a HEPA filter, I must say that I’m quite satisfied with the filter quality, overall performance, and efficiency of this air purifier.

Pre-filter

The pre-filter is the first stage of filtration.

It’s designed to capture large particles while protecting and extending the lifespan of the main filter.

It effectively traps larger particles, such as dust, hair, and similar debris.

What I particularly like about this filter is that it’s washable and easy to clean.

Additionally, I like that it’s available in multiple colors, meaning you can easily adapt it to your place by selecting a different color for the pre-filter.

Particle Filter

The main filter in this air purifier is a particle filter. It captures small airborne particles such as dust, pollen, allergens, mold spores, and similar.

I strongly believe that the particle filter is the most crucial filtration stage and that it played a significant role in the air purifier’s strong performance in our tests.

It’s important to note that Blueair doesn’t use a traditional HEPA filter.

Their particle filter has a lower density than HEPA filters. However, thanks to the electrostatic charging technology (HEPASilent), it achieves equal or even better performance than air purifiers that use classic HEPA filtration.

Activated Carbon Filter

The third filtration stage is the activated carbon filter.

This is a fibrous filter coated with carbon, but it doesn’t contain a high amount of carbon, which is likely why it didn’t perform exceptionally well in our odor neutralization tests.

However, if you need better odor neutralization, instead of switching to a different brand/device, you can simply upgrade to Blueair’s Smoke Stop filter, which contains a higher amount of carbon.

Ionizer (HEPASilent)

HEPASilent™ is Blueair’s proprietary air purification technology, which combines mechanical and electrostatic filtration to effectively remove airborne particles from indoor environments.

This dual-filtration system captures at least 99.97% of airborne particles as small as 0.1 microns, including dust, pollen, mold spores, bacteria, and viruses.

The process works by charging airborne particles with an electrical charge, which allows them to adhere more easily to the particle filter.

It’s important to note that this ionizer produces only 2.0 ppb of ozone, which is far below the allowed limit. Additionally, it’s certified by the CARB and Energy Star, which is another confirmation that the Blueair 511i Max is safe to use.

Regulations permit air purifiers to emit up to 0.050 parts per million (50 ppb) of ozone, meaning the Blueair HEPASilent™ technology operates well within safe levels.

How to Replace the Blueair 511i Max Filter?

This air purifier uses four-stage filtration technology, but you only need to replace two filters: the particle filter and the activated carbon filter.

The pre-filter is washable, while the HEPASilent™ technology functions as an ionizer and doesn’t require replacement.

A filter reset indicator is located at the top of the device. This small light turns red when it’s time to replace the filter.

For a more convenient way to track filter life, you can also monitor its status through the smart app.

The filter replacement process is straightforward and involves just a few simple steps.

Setup and Installation

The Blueair 511i Max doesn’t require any special preparation before its first use.

It comes with the filter pre-installed and is ready to use right out of the box. All you need to do is place it in your desired location, plug it in, and turn it on.

When positioning your air purifier, make sure not to block the airflow inlets or outlets, as this could potentially damage the device and significantly reduce filtration efficiency.

Design

The Blue Pure series features some of the most aesthetically pleasing air purifiers I have ever seen.

I really like its elegant design, fabric pre-filter, and minimalist controls. I’m sure that the Blueair 511i Max will blend seamlessly into almost any environment.

The build quality is solid, with high-quality plastic that feels durable and resistant to wear. This air purifier is built to last.

My only complaint is that it lacks a handle or a sloot for carrying, which makes it difficult to move from room to room.

The Blueair 511i Max can be thought of as consisting of two main parts:

the upper part, which houses the motor, controls, air quality sensor, and air quality indicator. The lower part, which contains the filter.

Overall, the Blueair 511i Max is a modern, stylish, and well-designed air purifier.

Controls and Indicators

The control panel is located at the top of the Blueair 511i Max.

Here, you’ll find two touch-sensitive buttons and LED indicators for operating modes, WiFi status, and the filter reset indicator.

The buttons are well-arranged, responsive, and easy to use. While they provide full control over the device, I highly recommend connecting the Blueair 511i Max to the smart app, as it significantly enhances ease of use.

With just two buttons, you can control essential functions such as power and fan speed adjustment. Additionally, you can adjust brightness, enable or disable the child lock, reset the filter, toggle WiFi on or off, and even perform a factory reset.

Airflow

The Blueair 511i Max is a cylindrical air purifier with air inlets located at the bottom of the device.

The filtered air exits through the fan grilles at the top.

Size and Dimensions

The dimensions of the Blueair 511i Max air purifier are 10.6 x 10.6 x 18.9 inches (26.9 x 26.9 x 48 cm), and it weighs just 2.84 lb (1.29 kg).

Overall, it is a very compact air purifier that can easily fit into any space in your home.

What’s in the box?

When you buy the Blueair 511i Max, you will get the air purifier, a pre-installed filter, and a user manual.

Features Overview

Although the Blueair 511i Max may appear to be a minimalist air purifier at first glance, it offers plenty of advanced features that become available when connected to the smart app.

However, some basic functions are still accessible without using the app.

Air Quality Sensor & Indicator

The Blueair 511i Max is equipped with an air quality sensor located at the back of the device, which detects PM2.5 particulate matter in real time.

One feature I particularly like about this sensor is that it continues to work even when the air purifier is turned off. This means that you can check air quality data through the smart app at any time, regardless of whether the air purifier is running or not.

This sensor works in combination with several other features, including auto mode, the air quality indicator, and the smart app.

The air quality indicator is a small LED light located on the front of the device, which changes color based on the current air quality in the room.

Color	Air Quality
Blue	Excellent air quality.
Green	Good air quality.
Yellow	Moderate air quality.
Orange	Polluted air quality.
Red	Very polluted air quality.

As shown in the table above, the air quality indicator lights up in five different colors, each representing a specific air quality level.

However, for a more detailed air quality analysis, including the exact PM2.5 particulate matter count, you will need to use the smart app.

Although the air quality sensor is a notable feature, I must point out that its accuracy isn’t as high as that of professional sensors, such as the Temtop air quality monitor, which we use in our tests.

Auto Mode

Auto mode is another feature that works in combination with the air quality sensor.

When enabled, the Blueair 511i Max reads real-time air quality data and automatically adjusts the fan speed based on the current air quality.

I find this feature useful, even though the air quality sensor isn’t as accurate as I would prefer.

Night Mode (Sleep Mode)

When in night mode, the Blueair 511i Max will dim all the lights and switch to sleep mode, operating at the lowest fan speed.

It produces a noise level of 40.1 dBA in night mode, making it an excellent choice for bedrooms.

Customizable Design

Personalize your space with customizable colors designed to seamlessly blend into your surroundings.

Available colors include Stockholm Fog, Moss, Sand, and Limestone.

Buying an extra pre-filter is an affordable way to style your air purifier, allowing it to better match your space.

Warranty

The Blueair 511i Max initially comes with a one-year warranty.

However, you can extend the warranty for free by simply registering your air purifier on Blueair’s website.

With the extended warranty, you can enjoy up to three years of coverage for your device.

Blueair Smart App

The Blueair smart app is one of the most complete air purifier apps I have seen so far. It’s avaliable for Android and iOS devices.

This app allows you to remotely control your Blueair 511i Max, giving you access to various features, including fan speed adjustment, real-time air quality monitoring, PM2.5 particulate matter tracking, filter indicator reset, brightness control, and scheduling.

One feature I particularly like is the ability to monitor PM2.5 levels, but what I find even more impressive is that the app stores air quality data, allowing you to review daily, weekly, and monthly trends, rather than just viewing real-time data.

To adjust the fan speed, you use a slider, which not only lets you switch between predefined speeds but also allows for customized speed adjustments. This means that, in practice, the Blueair 511i Max offers more than just the four preset fan speeds, providing greater flexibility.

However, there are a few areas that could be improved. For example, the scheduling feature is essentially just an advanced timer, rather than a truly smart scheduling system. I would love to see Blueair add an option that allows users to set schedules based on real-time air quality conditions.

Another standout feature in the app is “Clean Air ETA“, which estimates the time needed to purify the air in your room by analyzing real-time indoor air quality data from your connected Blueair air purifier.

Overall, I really like the Blueair smart app and believe it’s a fantastic addition to this minimalistic air purifier. It significantly enhances the value of the Blueair 511i Max and makes it even more user-friendly.

FAQ on Blueair 511i Max