A heating, ventilation and air-conditioning (HVAC) system can help to keep you comfortable year-round, but regular maintenance is a must to keep it in excellent working order. At the top of the list of essential components is a good filter to improve breathability by catching pollution in your home’s air and preventing debris from entering the unit and damaging it from the inside. First of all, the size of the filter needs to precisely fit the HVAC machine’s requirements. If it’s too small, it won’t keep dirt and dust out of the air vents. You’ll also need to be aware of the MERV (Minimum Efficiency Reporting Value) of the filter and decide whether you’d prefer it to be pleated or fiberglass. That’s a lot of variables, so let’s explore.