Answers to Five Common Home Air Filter Questions

What Size Air Filter Do I Need?

Filters come in many different sizes and grades, which can be a headache for homeowners who are trying to choose the right one at the hardware store. There are fiberglass filters, polyester and pleated filters,high efficiency particulate air (HEPA) filters and even washable air filters.They also come in a huge variety of sizes, ranging from 10 by 20-inch filters to 25 by 25-inch filters, with depths of one to six inches.

One of the most important things to check before you buy new filters is the size, because units generally only accommodate one filter size.Most filters have the size printed on the cardboard frame of the filter.However, if you have a filter that doesn’t display filter size or the numbers are too worn to make out, you can measure it yourself.

Just measure the length, width and depth of the filter with a tape measure. If your filter is 14 inches long, 20 inches wide and 1 inch deep the filter size you need to buy is 14x20x1.  

What Problems Can a Dirty Furnace Filter Cause?

A system with a dirty, clogged air filter must work harder to deliver the same cooling or heating results. This increases your energy costs and results in excessive wear and tear.

In addition to costing you extra due to increased energy use and decreased system longevity, everyone in your home will end up breathing dirty air.

Do All Houses Have Air Filters?

If a home has an air conditioner or heater it will have an air filter. However, knowing a home has an air filter that needs replacing is only half the battle – you still have to locate it.This can be a lot more difficult than you’d assume it should be.

Most systems have the filter located directly inside there turn duct. This allows any air being pulled into the system to first pass through the air filter for cleaning. Try to find the grill in your home that is pulling in air instead of pushing it out. It likely has latches to allow for easier access instead of just screws like most vents.

On some units, the filter may be attached to the air handler itself. Horizontal HVACs may have the return duct on the side of the unit, and the filter may fit in a slot on the side of the system.

If you have a vertical air handler, such as in a closet at the end of a hall, and the return air duct enters through the top of the system you may find the slot for the air filter located above the unit. Conversely, if the air return on your vertical air handler is below the unit the slot for the air filter will be there.

If your home has multiple returns you may need to replace air filters in all of them.


What’s the Best Air Filter For My AC or Furnace?

If your primary concern is air quality you should seriously consider investing in a HEPA air filter. These high efficiency air filters remove up to 98 percent of the pollutants that may be circulating throughout your home. Families with members who suffer from severe allergies, asthma or any kind of respiratory issues can especially benefit from an investment in HEPA filters, which will ensure the air circulating in your home won’t aggravate any underlying health issues.

The most common types of air filters are known as mechanical air filters. They can trap debris and dust as air is sucked into the return and prevent it from circulating throughout your home. The filtering effectiveness of these filters is measured by its minimum efficiency reporting value (MERV).The cheapest air filters you can find will have low MERV ratings – usually between one and four, while a HEPA air filter will boast a MERV rating in the 17 to 20 range.

If your main concern is cost and no one in your household suffers from breathing issues, you may want to go with a cheaper fiberglass or pleated air filter with a low MERV rating. If you’re more concerned with the air quality in your home you may want to purchase high-efficiency air filters or HEPA air filters.

Here is a rough performance estimate to give you an idea of the difference:

·       Fiberglass air filters (1 – 4 MERV): Remove 10 percent of air pollutants or less

·       Pleated air filters (10 – 13 MERV): Remove up to 45 percent of air pollutants

·       High-efficiency air filters (14 – 16 MERV):Remove up to 85 percent of pollutants

·       HEPA filters (17 – 20 MERV): Remove up to 98 percent of pollutants


Can I Run My Home AC or Furnace Without a Filter?

You really shouldn’t be running your air conditioner or furnace without a filter. Running your air conditioner or heater without a filter will definitely cause your indoor air quality to suffer significantly, as nothing is going to be filtered out of the air circulating in your home. In addition to just circulating dirty, dusty air in your home, you’re also jeopardizing the efficiency and health of your HVAC system.

Your air conditioner especially requires unrestricted airflow to the evaporator coils. The coils contain the cold refrigerant and absorb the heat from the air blowing over them. If the coils are caked in dust they can’t effectively absorb heat from the air and run the risk of freezing over entirely.

Get Your Questions About Air Filters, Heating and Air Conditioning Answered by San Antonio’s Experts

The heating, cooling and plumbing experts at Aramendia have been meeting the air conditioning and furnace installation and maintenance needs of San Antonio families for three decades. We really know HVAC systems, so if you have questions about air filters, thermostats or any other aspect of your heating or cooling system, our experts can help. Contact us to schedule seasonal maintenance, repair or anything else by calling (210) 654-1034.

5511 Brewster St.
San Antonio, TX 78233

About Us

Aramendia has been serving San Antonio
and the surrounding areas for over 29 years and we pride ourselves on the trust and reputation we have earned over that time. Our loyal customers know us as a reliable and trustworthy service company that will quickly send a highly-qualified technician to their home or office to take care of them.  In August of 2017, Aramendia became part of the Service Experts family. As a Service Experts company, Aramendia will continue to serve San Antonio and the surrounding area.