Once you’ve changed your filter, the “Check Filter or “Check Pre-Filter” light will remain on until it’s reset. While the air purifier is powered on, press the lighted button and hold for approximately 2 seconds until the light turns off. If the HPA3300 is too expensive, I’d recommend our budget pick, the Lasko LP300. It… Continue reading Honeywell HPA3300BV1 PowerPlus Air Purifier Review 2021