The answer to 'how to fix air filter' is to regularly replace or clean your HVAC air filter. This is an important maintenance task that helps keep your heating and cooling system running efficiently and improves indoor air quality. Replacing a dirty air filter can lower your energy costs and extend the life of your HVAC equipment.
Depending on the type of filter you have, you'll either need to replace it with a new one or clean it and put it back in place. Disposable filters should be replaced every 1-3 months, while reusable filters can be washed and reinstalled. Be sure to turn off power to the HVAC system before removing the filter.