what is the difference between the B400 and the HM400 units?

no difference, they are the same thing. Austin Air uses both for the same unit.

Mine seems to thrum unevenly, as if the motor is off balance. Is that normal?

Mine does this occasionally, especially after switching from a higher fan speed to a lower one. It usually normalizes within a few minutes though.

how many square feet does it cover?

1500 sq ft on high. This should used more for comparison levels because most of the time you should run the unit on low or medium. Normally we recommend to our clients to run on high for a few hours when they first get it and then low to medium. If something happens to give a high contaminant in the area, then raise to high temporarily to alleviate the situation. We also recommend to over not run right up to your room size limits. More air changes are better than fewer. Lastly, keep in mind that walls, doors, furniture obstruct airflow too. — Thank you, Barb Lulay at USAirPurifiers.com

Desertcart Logo

Deliver to Malaysia

For best experience Get the App

DOWNLOAD THE APP

WE SOURCE ITEMS FROM

UAE
UK
India
USA
Japan
KOREA

Customer Services

About Us

Customer Support

Common Questions

Are the products genuine and authentic?+

Yes, all products are sourced directly from authorized retailers in the US, UK, UAE and India. We maintain strict quality control processes and verify each product before shipping. All items come with applicable manufacturer warranties and are covered by our standard return policy.

How long does delivery take and is it reliable?+

Delivery times vary by destination country, typically ranging from 3-9 business days. Each order is fully trackable through our system. We handle all customs clearance and use reliable courier partners for last-mile delivery. You'll receive regular updates about your order status via email and our app.

What is Desertcart? Is it safe to order from?+

Desertcart is an international e-commerce platform operating since 2014. We securely process thousands of orders globally each day. Every product goes through our quality verification process before delivery, and we provide end-to-end order tracking, 24/7 customer support, and a comprehensive returns policy to ensure a safe shopping experience.

How is product pricing calculated?+

Our prices include the product cost, international shipping, import duties, customs clearance, and local delivery charges. We handle all customs and import procedures, ensuring there are no hidden fees upon delivery. PRO members receive additional benefits including free shipping.