Most people rely on air filters to reduce indoor air pollution, but some of them can also reduce airflow. This can be due to the filter being dirty, inefficient, or too efficient. Yes, it is possible for an air filter to be too efficient and restrict airflow to your HVAC system.
However, all air filters will restrict airflow to some extent.It is important to find the right filter for your unit and overall system in order to reduce the amount of contaminants in the air as much as possible.
If a fine filter restricts airflow too much, it can cause the air conditioner to turn off. A dirty filter that slows down airflow can also put stress on the system, making it unable to provide enough heating or cooling to the home.
Pleated air filters are known for restricting airflow, as they capture a lot of contaminants. This causes the fan to work harder, reducing efficiency and potentially leading to liquid returning to the compressor and premature equipment failure.
It is recommended that you clean or replace your air filter every 30-90 days depending on the type of filter and how well your system works.
MERV values vary depending on the type and size of the filter media, so it is important to do research before buying a filter. Low-MERV filters (think MERV 1-4) filter relatively few particles compared to high-MERV filters (think 11-1). Deeper pleated filters allow dirt to spread over a larger surface area, reducing pressure drop and allowing for less frequent filter changes without significantly affecting system performance.
A dirty filter means that the air moves slowly, which increases the operating time of the central air conditioning system and generally results in cooler air.