How Often Should an HVAC Filter Be Replaced?

HVAC Abilene, TX

Changing the HVAC filter is essential to keep the system working efficiently and keep energy costs down. Many homeowners often forget about this routine and end up with higher energy bills and possible maintenance issues eventually. In this article, you will learn how often to replace your HVAC filter.

When to change an HVAC filter

The answer to that question depends on a few factors. Usually, the recommendation is 30 days for less expensive fiberglass filters (less efficient) to as long as six months for premium pleated filters. These estimates factor in average use and the type and size of the filter.

The basic rule for pleated air filters is to change the filter every three months. As the filter traps dust, dirt, and allergens from the air, it becomes less efficient. The following are factors to consider to know how often to replace the HVAC filter:

Case of asthma and allergies

People suffering from asthma or allergies are more sensitive to airborne particles. If such people live in the home, then it is advisable to change the air filter every six weeks to preserve air quality in the house.


Cats and dogs shed hair and have odors that can accumulate in the house. Therefore, it is necessary to replace the filter every two months. Typically, cats and dogs shed more when winter turns to spring and summer turns to fall, which are important times to change the filter.

Young children

If there are kids in the house, high indoor air quality is paramount. To keep the home clean and air quality at its best, it is advisable to replace the filter every two to three months.

Factors affecting the lifespan of HVAC air filter

The following are factors that may affect the durability if the air filter:

The usage rate of the HVAC system

People living in a temperate climate who use the HVAC system for only a few hours a day can use the filter throughout the season or year. If the HVAC system is continuously running all year round, it is necessary to replace the filter every few weeks.

The size of the home

HVAC in smaller homes pumps less air for the same level of temperature change, which may mean changing the filter less frequently. Sometimes the devices are fitted with smaller filters, and therefore, need to be replaced just as frequently as filters in bigger homes.

The air quality in the house

If the air quality within or outside the home is poor, homeowners may need to replace their air filters more frequently to maintain the good air quality in the house.

In conclusion

The HVAC filter will trap dirt as long as it is in use. That is its function. Take the filter out every few weeks to examine it. Once the filter has a visible layer of dirt on it or a musty odor, then you should consider replacing it. The cost of replacing the filter is cheap and usually worthwhile when the energy bill comes in.

Request an appointment here: or call Bevills Plumbing, Heating & Air Conditioning at (325) 225-4115 for an appointment in our Abilene office.