Timely replacement of your IQAir air purifier filters is what ensures the air in your home is always clean. Since each filter of all IQAir air purifiers is separate (no combo filters), you always know you're getting the most from each filter. Change indicators are standard with every IQAir model. When the indicator light turns yellow/orange on the control panel, it's time to order your replacement filter. When it turns red, it's time to actually change the filter! Filter replacement times will vary depending on usage and conditions in your home, but general filter replacement times are listed for each IQ Air filter. Find each filter you need to keep your home cleaner, and as usual, all orders over $150 receive free shipping.