Carrier Smart Air Purifier XL review: It's powerful, but not so smart

The Carrier Smart Room Air Purifier XL is an excellent appliance, but given its DOA mobile app, you might want to give up the smart features and remote control and buy the "dumb" but otherwise identical Carrier Air Purifier XL, instead–for $120 less.

$550

Carrier is one of the world's biggest names in air conditioning, so it stands to reason the company would branch out into standalone air purifiers. But if you’re imagining a pint-sized purifier you can stick in the corner of the bathroom, think again. Carrier's Smart Air Purifier XL measures 31 inches tall (without the optional casters) and weighs on the order of 30 pounds. While Carrier conservatively says the purifier serves rooms of up to 560 square feet, it's clear there's power to spare here for much larger spaces, considering it can process up to 378 cubic feet of air per minute.

The specs are impressive, with CADR rates of 365 cfm (smoke), 385 (dust), and 427 (pollen). With 18(!) different speed levels plus turbo and auto modes, it is endlessly and perhaps overly tweakable—and surprisingly—not as loud as most other large units on the market, even at maximum throughput. A huge cylindrical HEPA filter (level unstated) sucks in air from 360 degrees around the unit, emitting clean air upward and out through the top.

This review is part of TechHive's in-depth coverage of the best air purifiers.

A large display on the top of the Carrier Smart Air Purifier XL reports PM2.5 levels in your home. The LED light ring around it changes color to provide at-a-glance feedback, glowing green, yellow, orange, or red as your indoor air quality becomes increasingly unhealthy.

Christopher Null/Foundry

A sizeable display in the center of the exhaust grille reports PM2.5 levels with a numerical value, plus a colored ring that offers an at-a-glance look at air quality. This ring shifts from green to yellow to orange to red, based on both PM2.5 and a more qualitative measurement of VOC levels. This display can be left flush against the top, so that it's facing upward, or popped up at an incline to be more visible from afar. Additional controls include a night mode and a separate LED-off function. All these controls are also available on the included remote control, though I found it only has about 20 feet of range, limiting its utility.

Its filters, which cost a whopping $130 to replace, last an estimated 6 to 12 months, with a replacement indicator included on the control panel. It's an interesting process to replace the filter, involving the removal of a ring that wraps around the top of the purifier to allow the unit to basically split into two. The filter then slides out of the bisected device.

The Carrier Smart Air Purifier uses very large disposable HEPA filters that should last from 6 months to one year, but they’re expensive to replace: $130 each.

Christopher Null/Foundry

Up to this point in my experience with the unit, I had few complaints with the Carrier XL. It's powerful yet reasonably quiet, and while the remote isn't all that useful, it isn't overly necessary. Then I tried to set up Carrier's mobile app, and everything fell apart.

The Carrier app looks innocuous enough, but you need only tap the "Add Device" button to drop into a nightmare of misguided app design. It starts with an archaic Bluetooth configuration process that is needlessly complex and which failed repeatedly during my testing, forcing me to reset the unit multiple times (a process that involves holding down four buttons on the device simultaneously), and trying over and over again to get the thing to connect.

I eventually succeeded – on day four of my testing adventure. (Pro tip: When the app asks you to tap the Wi-Fi button on the purifier to confirm the connection, do it immediately—wait more than a couple seconds and the connection will time out.)

Carrier's mobile app reports the basics, but using it to add the air purifier to our Wi-Fi network nearly had us tearing our hair out.

Christopher Null/Foundry

Once I had the Bluetooth connection working, it was time to connect the purifier to my Wi-Fi network (only 2.4GHz networks are supported). This step resulted in an error message when I tried to give the purifier a name, but it turns out that step is optional. I force-quit the app and returned to it to find everything working. Well, sort of working. In regular usage, commands sent to the purifier are slow to be recognized, and the display within the app often doesn't match the messages on the hardware's own display. The app is also prone to freezing from time to time, again requiring a force-quit to get things back in sync.

The app does virtually nothing you can't do on the hardware directly, and even those duplicated functions don't work great all the time here. The countdown timer, for example, once decided to turn the purifier off after 5 minutes instead of the hour that I’d set. Sure, you get a measurement of outdoor air quality within the app and a percent-of-life estimate on your filter, but those are the only real added features. There's no logging function or historical view of indoor or outdoor air quality, no scheduling system, and no measurement of other pollutants besides what the unit itself provides.

On the plus side, you can control the device with Alexa and Google Assistant voice commands, but that functionality, as you might expect, is limited. Perhaps the best news is you can buy this unit without a remote and these smart features and save a $120 off the purchase price. That's a compelling discount that makes the unit competitively priced vs. larger purifiers like the NuWave OxyPure, which it even beats out on CADR rates, not to mention aesthetics.

Christopher Null is a veteran technology and business journalist. He contributes regularly to TechHive, PCWorld, and Wired, and operates the websites Drinkhacker and Film Racket.