Filters with a MERV rating of 17 to 20 are rarely needed in a residential home. A MERV rating of 13 to 16 is considered hospital-level air quality, so it's unlikely that your home will require more than that. The short answer is yes, but it's not really a problem, except in extreme cases. Most modern HVAC systems have no difficulty working with higher MERV filters, which is why millions of homeowners rely on them. The main risk of high-efficiency air filters comes from the fact that they are not changed regularly.
If you keep up with replacing filters, you are unlikely to experience any filter-related issues with your HVAC system. The AC coil inside or near your oven or air handler cools down significantly as it draws heat from the space and pumps it out. A normal flow of hot air over the coil will prevent its surface from dropping below 32F. Low airflow allows the coil to cool like ice, and then the moisture in the air freezes and the coil is encased in ice. At this point, the air conditioning system cannot do its job.
The purpose of using a MERV 12 or higher filter is to achieve better IAQ: cleaner, more breathable air for everyone, and especially for those with allergies, asthma, COPD, etc. If you are in a situation where you should not use a high MERV filter (12+) for use in ovens or air conditioners and would like to research air purifiers, here are two suggestions. Typically, a filter with a higher MERV rating will reduce airflow. However, there are many other factors at play, such as the size of the filter and the type of fan motor in your HVAC system. A MERV 11 air filter has a higher efficiency rating. That is, it can capture finer particles and remove more pollutants from the air.
But is MERV 11 too high for your needs? Good luck with your decision to use higher MERV filters in the future. Of course, they're not a bad thing. Reducing the amount of dirty particles in the air of your home is a very common request. It's only important to make sure that the rest of the system is configured to handle the increased restriction that filters create. A MERV filter 13 is likely to help if the goal is to prevent droplets from passing through.
However, if you are concerned about outdoor air pollution, family members with respiratory problems, or pets in the house, then a higher MERV rating might be a good idea. MERV 8 air filters are almost as affordable as less efficient products, making them good value for money. In addition, most low-capacity air handlers are unable to mount the static pressure required for high-MERV filters, so CFI configurations with these often require in-line boost fans. I have three MERV-13 filters in my house and the pressure drop in all of them is less than 0.06 i. MERV 11 air filters are slightly more expensive than a standard filter, but paying a few dollars more per filter is generally worth the extra efficiency. In particular, using an air cleaner with a MERV rating that is too high can damage the compressor, heat exchanger, and air conditioner coil. MERV ratings determine the capabilities of an air filter and its level of filtration efficiency.
If you want it to at least clean the air and handle dust, mold, pollen and bacteria, then a MERV 8 will do its job. I want to introduce a carbon filter; however, the only problem is that it has a Merv 8 rating. Going up just three levels of MERV rating can be either a smart move that makes air cleaner or a detrimental option for your entire HVAC system when considering airflow MERV 8 vs MERV 11 capabilities.
