How often should I change my filter?

How often a person should change a filter depends on the household conditions. 1″ filters should be changed every 3 to 4 weeks, 4″ media filters every 4 to 6 months, or high efficiency filters every 6 to 12 months. Keeping your filters changed regularly is a must; not doing so will put a strain on your air conditioning unit and cause unnecessary repair work down the road.