AirDoctor 3500i Review: Data-Driven Testing

In This Review
Purification Performance | Ozone Test | Filters | Coverage | Build Quality | Noise Test | Usability | Maintenance | Size | Specs | Product Evolution | Comparison | FAQs

Performance Summary

At Modern Castle we test 11 different factors that impact the performance, build quality, and usability of the air purifier. Below is a complete list of our testing categories and their performance.

Test Type	Test Data
PM2.5 (1 hour test)	0.1 ppm
PM10 (1 hour test)	0.2 ppm
Particles (1 hour test)	15
AQI (1 hour test)	1
Ozone Detected	0.0 ppm
Filter Type	HEPA, Carbon, Pre-Filter, Ionizer
Coverage Area	1,274 sq. ft. (118 sq. m.)
CADR	340 CFM
Max Wind Speed	15.6 mph (25.1 kph)
Noise Test	66.8 dB

To test the purification performance of the AirDoctor 3500i, we placed it in a medium sized room in our office (~14’ x 10`). Next, we lit incense to introduce smoke and other particulates into the air for 30 seconds. After, we use a professional air quality detector to take a measurement of the smoke filled air.

Next, we run the air purifier on the highest fan speed for 1 hours, taking measurements of the air quality at the one hour mark and the end of the test. Here is what we found:

Performance Metric	Starting Measurement	After 1 Hour	After 2 Hours
PM2.5	58.4 ppm	0.1 ppm	0.1 ppm
PM10	98.8 ppm	0.2 ppm	0.1 ppm
Particles	10053	15	11
AQI	152	1	1

In our air purification tests, the AirDoctor 3500i was able to reduce PM2.5 to 0.1 ppm. This is 0.39 PM2.5 lower than the average of 0.49 ppm PM2.5, based on all of our air purification tests to date.

Below, we’ve included information on the testing criteria and what defines good vs. bad air quality. Simply, the lower the numbers the better.

This level of purification power is something we similarly see in larger air purification systems. With this being a step down in terms of coverage area from the larger AirDoctor 5500i model, it didn’t sacrifice any of the purification power when packed into a smaller device.

With most air purifiers ozone generation isn’t an issue. That said, some that use negative ion generators have the potential to create ozone. To test this, we run the AirDoctor 3500i, letting it run for 1 hour and measure the levels of ozone before and after with an ozone meter device.

In our ozone tests, the AirDoctor 3500i generated 0 ppm. This is the same level as the average of 0 ppm, based on all of our ozone tests to date.

Unfortunately, there are no 3rd party filters available for AirDoctor. So you’ll need to buy the 1st party AirDoctor filters.

Coverage

The AirDoctor 3500i has a coverage area of 1,274 sq. ft.

Comparing the AirDoctor 3500i to the average, we see it has a notably larger coverage area. Across all air purifiers we’ve tested to date, the average coverage area is 749.19 sq. ft. and the average CADR is 292.49 CFM.

Wind Speed Test

Our wind speed test uses an anemometer placed directly on the air vents of the AirDoctor 3500i to measure the fan speeds in miles per hour. We run it on the lowest and highest fan speeds and record the speed of the air coming out of the device.

In our wind speed test, the AirDoctor 3500i was able to generate a maximum wind speed of 15.60 mph. This is 3.32 mph higher than the average of 12.28 mph, based on all of our wind speed tests to date.

The wind speed on the AirDoctor 3500i is definitely something to consider for this medium-sized air purification system. For context, the size above the 3500i is the 5500i, which is meant for larger areas, and has the same wind speed as the 3500i.

Our build quality test is a subjective test where we examine and assess the major material and design components of the air purifier. Specifically, we are looking for build and design issues that are more likely to break and/or be difficult to use.

Part	Build Quality
Overall	Exceptional
Body	Excellent
Fan	Exceptional
Filters	Exceptional
Controls	Exceptional
Display	Excellent

AirDoctor is a fantastic brand that builds reliable air purifiers out of sturdy plastic components. With the 3500i, you get a glossy white finished plastic that surrounds the body. It feels well put together and gives the impression that it’s built to last. Overall, the AirDoctor 3500i demonstrates exceptional build quality.

To determine the level of noise that the AirDoctor 3500i creates we use a sound meter and measure the decibel levels on both the lowest and highest fan speeds. In addition, we measure the ambient noise levels of the room as a baseline comparison.

In our noise tests, the  AirDoctor 3500i generated 66.8 dB of noise at the max fan speed. This is 4.65 dB lower than the average of 62.15 dB, based on all of our noise tests to date.

Due to the higher wind speeds the AirDoctor 3500i creates, it carries a louder noise level. However, the noise level output is not that far off when compared to the average. To put this into perspective, our current testing data ranges from 72.50 dB to 46.00 dB. The AirDoctor 3500i is fairly close to the testing average when looking at the overall range.

The major update to this model is the wifi connectivity, allowing it to connect to AirDoctor’s app.

Setup was simple and easy. The most important step you’ll need to take with your new AirDoctor 3500i is removing the plastic cover from the filter.

This is a critical step that must be done before turning on the system.

The controls on the AirDoctor 3500i are at the top of the system and displayed with a backlight panel. When pressing the buttons, they make an audible “beep” to signal the user that it has registered your input.

On the front of the air doctor, is the air quality indicator with an LED light ring. This ring will display the air quality index with either blue for good air quality, orange for moderate, and red for poor air quality.

Wireless Controls

What sets this model apart from the standard AirDoctor 3500 is its new Wi-Fi capability and app connection. The AirDoctor App allows you to remotely manage your Air Doctor’s performance and power settings. The app provides details about the air quality in your room and local weather information.

In The Box

• AirDoctor 3500i
• 1xHEPA Filter
• 1xCarbon Filter
• 1xPrefilter

The AirDoctor 3500i has an estimated yearly maintenance cost of $120. The following are the major maintenance tasks for the AirDoctor 3500i.

Task	Description	Est. Annual Cost
HEPA Filter	Replace Every 8-12 Months	$59.95
Carbon Filter	Replace Every 8-12 Months	$59.95
Pre Filter	Periodically clean and replace as needed	$19.95

Size & Dimensions

The AirDoctor 3500i has the exact same dimensions as the AirDoctor 3000.

Attribute	Measurement
Height	18.7″ (47.5 cm)
Length	8.8″ (22.2 cm)
Width	13.9″ (35.2 cm)
Weight	18.0 lbs. (8.2 kg)

Specifications

The following table details the product specifications according to the manufacturer.

Manufacturer Specifications
Manufacturer	AirDoctor
Model	AD3500i
Height	18.7″ (47.5 cm)
Length	8.8″ (22.2 cm)
Width	13.9″ (35.2 cm)
Weight	18.0 lbs. (8.2 kg)
Filter	HEPA, Carbon, Pre-Filter, Ionizer
Noise Levels	66.8 dB (max)
Coverage Area	1,274 sq. ft.
CADR	340 CFM
Wi-Fi Compatible	Yes
Warranty	1 year
Price	Check Price

Product Evolution

The new AirDoctor 3500i is the new series from AirDoctor that has the app connectivity. The Airdoctor 2000i, 3500i, and 5500i all come with Wi-Fi features that connect to a very informative app.

How does AirDoctor 3500i compare?

Below is a complete list of our air purifier tests and critical product data compared side by side to the average based on all of our air purifier tests to date.

Test Type	Test Data	Avg. Data
PM2.5 (1 hours)	0.1 ppm	0.49 ppm
PM10 (1 hours)	0.2 ppm	0.74 ppm
Particles (1 hours)	15	61.04
AQI (1 hours)	1	1.91
Ozone Detected	0.0 ppm	0.0 ppm
Filter Types	HEPA, Carbon, Pre-Filter, Ionizer	n/a
Coverage Area	1,274 sq. ft.	744 sq. ft.
CADR	340 CFM	291 CFM
Max Wind Speed	15.6 mph	12.4 mph
Noise Test	66.8 dB	62.2 dB

Generally, a strong indicator that the air purifier has exceptional purification performance is our 1-hour testing measurement. At 1 hour, the AirDoctor 3500i was able to reduce the PM2.5 to 0.1 ppm, easily beating our 1-hour testing average of 0.49 ppm. It had similar measurements for PM10, reducing it to 0.2 ppm after the 1-hour measurement. It then held those measurements into the 2nd hour.

Additionally, the app connectivity stands out for the AirDoctor product lineup. Not only does it provide remote handling, but giving the extra air quality information sets it apart from other air purifier apps.

Other Air Purifiers to Consider

FAQs