The answer to 'how much to fix air filter in Illinois' is that the cost can vary widely depending on several factors. As an HVAC expert, I can provide some general guidance on what influences the pricing for replacing an air filter.
The main factors that affect the cost include the type of air filter (standard vs. high-efficiency), the size and accessibility of the filter, and whether you choose to do it yourself or hire a professional HVAC technician. DIY filter replacements are generally inexpensive, often costing $10-$50 for the filter itself. However, hiring a professional HVAC service can range from $50 to $150 or more, depending on the complexity of the job and your location within Illinois.