As an HVAC expert, I have encountered many homeowners who are unaware of the importance of furnace filters in their central heating and cooling systems. While all HVAC units require an air filter, some make it difficult to locate. The filter can be found in various places such as the air return grille, inside the air handler, or outside the air handler in a filter grille. In some cases, HEPA filters are installed as part of the central air system to improve indoor air quality.
For instance, my Lennox Ch35-42C-2F-3 indoor unit and Lennox Elite EL180UH090E60C-02 gas oven are equipped with HEPA filters to ensure clean air near the oven. When it comes to purchasing furnace filters, they can be found at hardware stores, home centers, warehouse clubs, HVAC stores, and online retailers. These filters come in standard sizes and are readily available for purchase. However, not all filters are created equal. It is important to choose the right filter for your specific HVAC unit to ensure optimal performance. All central heating and cooling systems require a fuel source, typically gas for the furnace and electricity for the air conditioner.
This means that regular maintenance and replacement of furnace filters are necessary to keep your HVAC system running efficiently.