How Often To Change Air Filter And Other HVAC Care Tips

How often to change air filter is something you should know. As a homeowner, it’s your responsibility to ensure your air filters work properly. You’ll need to replace your heating, ventilation, and air conditioning system (HVAC unit). Chances are your old filter needs to be changed.

Your air conditioning system is responsible for the air quality in your home. If you know how to change the air filters on your HVAC system, you’ll save money, and that’s why we’re here. We’ll show you how to change air filters so you can protect your home’s air quality. 

How Often Do You Change Air Filters

Air filters need to changed every 90 days on average. An HVAC filter will only last one to three months on average. Meaning you have to keep track of the date when you installed them. If you wait too long to change the filter, your indoor air quality will be impacted. 

A collapsed air filter can get lodged in your fan or make a big gap, causing air to float around the filter without it getting filtered. If your filter isn’t working, it can have adverse effects on your health and cause breathing problems, especially for those with pre-existing conditions.

When To Replace HVAC Air Filters

The type of air filter you purchase can also factor in how often you replace this essential equipment. With air conditioners, replace your filter every 30 days with cheaper fiberglass filters to avoid higher energy bills. For higher-end pleated air fibers, change them every six months.

When you buy a new air filter, the packaging will indicate how long it is expected to last. Still, the filter’s expiry date should be the maximum date to which you keep that particular filter. You should change your filter earlier than the packaging suggests.

However, it depends on the health conditions of those who live in your home. People with allergies will require new filters more than once a month for maximum efficiency. Also, if you have pets, they can take their toll on your indoor air system. 

Asthma And Allergies

You should change your filters often if you suffer from allergies or asthma. Respiratory issues make you much more sensitive to airborne particles, so you should change air filter every six weeks to ensure your indoor air quality remains at its best.

If you allow dander, dust, and other contaminants to accumulate on your air filter and find their way into your home, it can harm you. Symptoms like coughs, runny noses, sneezing, and others without a clogged filter. 

Weather Conditions

During flu and allergy seasons, upgrade your air filters to maximum efficiency filters. When you begin to observe an increase in air particles or pollutants, your filter should get changed more frequently.

Also, during home renovations, there is a chance dirt and dust circulating in the house will increase and block your filter. In such a situation, your home will require additional air filter changes.


How often to change air filter spray

Having pets can influence how you change your air filter. Pets cause an increase in dander, fur, and dust floating through the air in your home. These pollutants come together and end up blocking the flow of air in your filter.

If you have multiple pets, it can get even worse, and the build-up of fur, dust, and dander can impede the running of your HVAC. You should consider replacing your filter every four to six weeks if you are a pet owner.

House Occupancy

When your house is a vacation home where you spend a small amount of time yearly, the rules are different. Due to the absence of human activity during certain, fewer contaminants get trapped in your filter.

The fewer the contaminants, the less often you need to change the air filter. You can prolong the periods between a filter replacement. Most times, vacation homes get a change in air filters every six months. You can also put off changing your air filter less if you live alone and without pets. The fewer people in a house, the less time it takes to clog your filter.

Cut Repair Costs

Over time, your air filter accumulates dirt, dust, fur, and other contaminants that may be found around your home. Your once new, white, and clean air filter will turn dusty and gray as it begins to spend months in the return. This deterioration can have negative impacts on your HVAC system.

Changing your air filter is beneficial to the smooth working of your HVAC system. A dirty air conditioner can lead to the HVAC system undergoing extra work.

As time goes on, the strain on your unit will result in essential repairs or, even worse, cut short the lifespan of said unit. Changing your air filter will help keep the parts of your air conditioner clean, preventing it from wear and tear. You can save yourself money by simply changing your air filter routinely.

Conserve Electricity

During the summertime, your electricity bill can go up in astronomical proportions. Changing your air filter can help you cut down your bill.

When your air filter is clogged, the HVAC unit requires a lot of extra work to circulate fresh air throughout your home; the extra work calls for more electricity. More electricity means more bills.

Replacing your filter will help you reduce the amount you pay for electricity. Investing in a relatively inexpensive air filter and replacing the filter at the right time can save you a lot of money in repairs.

Better Air Quality

Studies have shown that the air in your home can be as much as two to five times more polluted than the air outdoors. When your air filter is clean, you do not have to breathe in particles and other different contaminants. 

How Do You Know It’s Time to Change Your Air Filter?

How often to change air filter spray

Air filters trap dirt. So, how do you determine when your air filter has trapped more than enough dirt and requires a change?

How To Change HVAC Filters

Replacing an air filter is easy. It is a straightforward process if you follow the following steps:

  1. Ensure that you turn off your HVAC system before you begin; this is very important.
  2. Find where your air filter is – you will most likely find your air filter where the air is sucked back from your home into your system (this is known as the return), which is either on your ceiling or wall with a grille covering it. If you do not find it there, it will be where your air handling unit is located, typically in your attic, basement, or closet. You will observe a small box that takes air into the unit.
  3. Remove the grill or open the box – if you own a grille, you will most likely find tabs that you can pull up, so you can take out the filter without needing a screwdriver.
  4. Locate the filter – the filter should carry the size or a model number printed on it to help you identify it and purchase the correct one. Ensure that you buy the correct size of the filter.
  5. Take out the dirty filter – observe the old filter when you take it out. If it is more contaminated than usual, this means you should change your filter more often than you already do. 
  6. Put in your new filter, close the box, or put back the grill – this is the final step. Make sure you note the date when you change your filter to keep track and know when next to change the filter. 

How To Buy A New HVAC Filter

You know you can find information like size printed on your current filter. However, you might still be unsure about what type of filter to purchase. Here are a few tips that can be of help:

  • Avoid buying cheap filters
  • You should buy a pleated filter with a sturdy wire mesh supporting it and preventing it from collapsing.
  • Your filter should not have a very high MERV (minimum efficiency reporting value) rating. A quality filter should have a MERV rating above eight or nine. This type of filter will take out most of the small particles that can trigger allergies and other respiratory issues.

How To Rate An Air Filter

For most people, the challenging part of changing your air filter is figuring out what kind of replacement you should get. This is why most companies refer to a particular scale while measuring the efficiency of their filters. This is called the MERV scale.

The Minimum Efficiency Reporting Value (MERV) scale gives professionals a uniform standard to use when rating their air filters’ quality. MERV is measured by exposing a clean air filter to different sizes of particles. Each particle is forced through the air filter six times using a sprayer. About 12 other particles are used to determine which air filters are best at trapping different air pollutants.

Based on this scale, there are 16 filter categories.

What Is A MERV Scale?

MERV 1-4

These are the lowest ratings on the scare, and they trap the least number of contaminants from the air in your home. MERV 1-4 filters can trap common particles such as carpet fibers, dust mites, pollen, etc. from the air.

Like their price point, their efficiency is low. This air filter class is excellent for homes on a budget where there are no occupants with respiratory problems.


MERV 5-8 filters are more effective than those in the MERV 1-4 category. They can work effectively in mold, finer dust such as cement, and even aerosol spray particles. Such filters are of higher quality and cost more than the primary category.

However, you should know that these air filters are unable to trap particles smaller than one micron.

According to experts, you should get an filter with a MERV score from 6 to 8 for the best performance. These filters are affordable and allow your HVAC system to function conveniently without any strain. When your unit operates smoothly, it keeps your power bill low while maintaining optimum air quality.

MERV 9-12

This filter class is considered very high efficiency. It can trap tiny particles from the air, as little as auto emissions. If you use air filters in this category, your HVAC system has to do extra work to circulate cooled air in your home. The weave of the air filters that fall in this class makes it a lot more difficult for the HVAC system to function seamlessly.

MERV 9-12 filters are perfect for people who have allergies; the downside is that it may negatively reflect your electricity bill.

MERV 13-16

A filter with this rating is categorized for maximum efficiency. They are more suited for commercial buildings than a home heating and cooling system. The filters capture particles as small as 0.3 microns, like tobacco smoke and bacteria. They can also safeguard against mold spores.

Other Considerations

Here are other things to consider when buying an air filter:


The return sizes differ among homes, so make sure you visually inspect the size of your filter.


If you do not like the idea of throwing your air filter away every two weeks, invest in a washable air filter. Although this may require extra work, it is a more environmentally friendly option.

Using a washable air filter is also beneficial because you can change it as you like while saving money on air filters. Washing your filter on a more regular basis will increase the quality of air inside your home.


The more pleats an air filter has, the higher the chances of removing air pollutants from your indoor air. In situations where you cannot find the MERV rating on the air filter packaging, you can look out for a filter with a lot of pleats per foot. Pleats are a great way to gauge the overall efficiency of an air filter.


What Are Washable HVAC Air Filters?

Washable HVAC filters have a MERV rating between one and four. They’re effective at trapping large airborne contaminants like dust, dust mites, carpet fibers, and pollen. Although more expensive, they help you save money in the long term.

On average, a washable filter costs between $30 and $200.

Is It Safe To Use The Same Air Filter For Both Heat And AC?

Furnace filters and AC filters are one and the same. All filters are categorized based on their intended use. During the summer months, you will need to search for AC filters, for example. So, it’s recommended to change your filters before each season.

Can Air Filters Catch On Fire?

A clogged air filter is a fire hazard. When an HVAC furnace filter is dirty and clogged, oxygen cannot travel through it. This could lead to a “flame rollout.” What this means is that flames will roll out from the furnace cabinet and consume more oxygen. When you run your HVAC in this condition, you increase the chances of it catching on fire.

To see if your filters are clogged, visually inspect them every two weeks. If you have more than one pet, then you can expect pet air to be a problem. 

Is It Okay to Use Your HVAC System Without a Filter?

It’s a bad idea to use your HVAC system without an air filter because your system wouldn’t be able to remove airborne particles and pollutants from your indoor air space. However, if you need to run your system without an air filter, you shouldn’t run it longer than six hours. But the practice isn’t advisable in larger homes.

What Is The Best Air Filter To Use During The Winter?

Fiberglass or synthetic filters are your cheapest options. The problem is how they provide minor protection for your indoor air. You can afford it, electrostatic filters would help you save money in the long-term as they only need to be changed every 90 days.

How Often To Change Air Filter Conclusion

Many homeowners know what to expect when changing HVAC air filters. Each home has different needs, and this includes your HVAC system. Keep in mind the occupants of your house. Even if you have one pet, you will need to change your air filters more. If you still don’t know how to change an air filter, you need to correct this today. 

You should inspect your air filters every week. If you notice a musty smell or that the filter is covered in dust change it. Filters are cheap, so if you doubt, it is better to replace them earlier than to wait.  

Your HVAC’s lifespan and health will be grateful to you if you adhere to the proper guidelines regarding when you should change your air filter. Check your air filter today, and replace it if it’s overdue and enjoy fresh, clean air in your home.