Q: what is the difference between the 311i Max and the 311i + Max?

A: The Blue Pure 311i+ Max air purifier cleans up to 1,116sqft large space in 30min on high and has a Clean Air Delivery Rate (CADR) of 300 for fine smoke particles, dust and pollen. The Blue Pure 311i Max air purifier cleans up to 929sqft space in 30min on high. This air purifier has a Clean Air Delivery Rate (CADR) of 250 for fine smoke particles, dust and pollen.

Q: If this Blueair purifier is set in automatic, it stays on at all times. Should it be turned off at intervals, or is it ok to keep it running at all times 24/7? Thank you.

A: Thank you for your interest in Blueair! Yes, your Blue Pure 311i Max air purifier can operate 24/7, and in fact, continuous use is recommended — especially when set to Auto mode, which automatically adjusts the fan speed based on real-time air quality. This helps maintain optimal indoor conditions.

Q: How good is this unit for removing dust and rate of air circulation

A: I have one cat, hardwood floors and two flat-weave wool carpets, a central HVAC system that is regularly serviced AND I vacuum and dust *everything* at least weekly. If I don't, there's a visible layer of dust on everything (this was true even before I adopted a cat). So: I purchased this unit three weeks ago in the hopes that it would reduce the dust so that I could go longer in between flat-out cleaning sprees-- and also so that my cat's allergies might improve. (Yeah, you read that right: my cat is pretty severely allergic to dust mites and I figured this air purifier is less expensive than a very unhappy cat and repeated vet visits.) So how's it going? The good: rate of air circulation is amazing, truly, especially on setting #2 or 3--and my place feels *fresher* when running it on those settings, if that makes sense. Running it at setting 3 while cooking is also *helpful* in keeping the place smelling fresh, but don't expect miracles-- maybe 50% better? Also: running it 24/7 on setting 2 or 3 isn't practical--it's both loud and windy. I generally leave it on Auto. The bad: my place is still seriously dusty. With the same amount of cat hair forming the same tumbleweeds. Honestly, I didn't notice much improvement on dust or hair, which was v disappointing. Lastly: my cat might be itching less? hard to tell if it's helping but it's not hurting. *My* allergies (pet dander, dust mites) seem to be exactly the same as before (I need benadryl ~2x week, so they aren't severe, ymmv). Do I regret my purchase? No. Do I wish this machine would improve the dust situation: yes.

Q: My house is 2 floors with a total of 1350 sq. ft. If I get one of these, better to put it on the 1st. or 2nd floor?

A: Thank you for your interest in Blueair! The Blue Pure 311i Max quickly cleans 439 sq. ft. in 12.5 minutes and 1,054 sq. ft. in 30 minutes. We recommend placing it on the floor where you spend the most time. For best results, consider having an air purifier on each floor to maintain consistent air quality throughout your home.

Q: Can anybody say if Blueair air purifiers have True HEPA filters? It says HEPASilent but is it the same thing? Their replacement filters do not seem to mention HEPA at all in the description. My Levoit units were stripped of HEPA labeling.

A: Thank you for your interest in Blueair! Our air purifiers feature unique HEPASilent™ technology, which combines traditional mechanical filtration with electrostatic charging to clean the air faster, produce more clean air, and do so much more quietly than conventional HEPA purifiers. This innovative technology, ensures maximum filtration with minimal noise, delivering clean, filtered air to your room as quickly as possible.

Q: This device keeps turning itself off after a couple of hours. This is a brand new device. I don't think this is normal, especially since I have other air purifier brands that I have kept on for months on end. What is the solution to this?

A: Thank you for reaching out about your Blue Pure 311i Max. I’m sorry to hear that you’re experiencing an issue with the unit turning off. Please contact us through the link below so our support team can assist you in resolving this: https://www.blueair.com/us/contact-us-page.html

Q: Does this omit any ozone? Is it safe around pets? Saw something from this year saying it omits some ozone and my dog has been coughing ever since I put 2 of these in our home. Are they safe? Should I return both?

A: Thanks for your question! Our HEPASilent™ technology uses mechanical and electrostatic filtration to quietly and efficiently remove pollutants. Our Blueair air purifiers, including the Blue Pure 311i Max, meet CARB standards, are certified to Intertek’s Zero Ozone standards, and are completely safe for pets. Their design won’t cause coughing, and we recommend checking with your veterinarian since every pet is unique. If you need further support, our team is always happy to help.

Q: Are these safe around pets? We have 2 and ever since we got these, one of our dogs has been coughing consistently, while the other does here and there. I want to make sure it’s safe or return them. Thank you.

A: We have a small dog and it has absolutely no effect on him.