This Is the Reason Your Air Conditioner Sucks, All of a Sudden

Air conditioning units can fail and falter for a number of reasons but one is most common and, luckily, it's the easiest to remedy. A clogged filter will stop your window AC or HVAC from sending chilled air into your face, and cleaning or changing the filter on your AC will give you far more cooling bang for your electricity buck.

Air conditioning is a figurative and literal live saver during these sweaty summer heat waves, but when your AC filter becomes gunked up with dust, pollen and pet hair, it reduces its performance and may even render the system completely useless. The filter is essential for keeping your breathing air free of debris so changing and cleaning it regularly will keep those temps down and your home's air clean. 

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Below we'll outline when to change your AC filter and how to swap it the right way to guarantee your AC unit runs properly and efficiently. For more, explore these six ways to save on air conditioning this summer and effective ways to lower your AC bills when on vacation. 

Read more: How to Clean Your Air Conditioner So It Runs Like New

Here's how to tell if your AC filter needs changing

The only real way to know it's time to replace your AC filter is by checking on it every so often. To do so, pop your AC filter out and hold it up to the light. If you can't see through the filter, then it's time for a new one. Below, find step-by-step instructions on how to change out your filter. 

How to change an AC home air filter

First things first: You need to locate it. It could be several places: in the air handler cabinet, return air duct or in a window AC unit, etc. 

Next, make sure you get the right filter size -- the dimensions are usually printed on the side of the filter – so you can make sure you're buying or ordering the right size replacement. 

Now, it's time to actually change the filter:

• Turn the power off. This will ensure that you don't touch live voltage or that debris be sucked into the unit. So, be sure to turn off power at the unit and also at the circuit breaker.
• Remove the old filter. Simply slide it out of the slot that holds it in place.
• Take note of its condition. Can you see through it when it's held up to the light? If not, definitely time to replace it. 
• Insert the new filter. To make sure you get it in the right way, make sure the arrow icon on the filter's frame points away from the return air duct and toward the air handler mechanism.

How often does an AC filter need to be changed?

Do you know off the top of your head the last time you changed your filter? If you can't remember, it has no doubt been too long. 

Many HVAC filters actually say on the packaging that a monthly check-in is ideal to keep dust and allergens to a minimum. For the most part, experts agree your filter will probably need to be replaced every three months or so, but monthly assessments can guarantee you don't leave a worn-out filter in your unit for too long past its effectiveness. 

Best Portable Air Conditioners of 2024 See at Cnet

Other factors that change the lifespan of your AC filter

Depending on a number of factors, such as your surroundings, the season and the inhabitants of your home, you may want to replace your air conditioning filter more or less often than once a month. 

Air filter type

Some air conditioning filters are made to last longer than others. But luckily, you don't have to do a ton of research or be an AC expert to know which brand is best. Just look at the packaging. 

All AC filters have a Minimum Efficiency Reporting Value (MERV) rating. The higher the MERV number, the better quality the filter is, meaning it can hold contaminants or debris more efficiently and therefore lasts longer.

The only downside to picking a filter with a high MERV rating is that it can slow down the airflow in your AC unit. The best filter options will have a balance between good quality and good airflow, which is typically a filter with a MERV rating between 6 and 8. If you have a high-efficiency AC unit, you may be able to get away with a higher MERV rating, but check the owner's manual just in case. 

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Geography

Geography and seasonality can also affect how often your filter will need to be replaced. Living in a dusty or more polluted environment calls for a new air filter at least once every three months.

For example, in desert climates, your AC is filtering out all that desert dust (in addition to 90-plus degree temperatures) to keep the air in your home pleasant to breathe. Your AC is likely working overtime, which means it'll need extra maintenance. 

Pets

What sort of creatures inhabit your household can also determine how often you'll need to replace the filter. If you're like me and have two long-haired pets living with you, checking your filter every three weeks is a good rule of thumb to prevent build-up. 

Usage 

If you live in a temperate climate and rarely turn your AC unit on, you can probably wait up to six months to change the filter. A simple way to remember is to switch the filter out once in the spring and again in the fall.

Watch this: Beat the summer heat with this DIY air conditioner

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An added incentive to change your filter

Not only can regularly changing your AC filter help improve your home's air quality and conditions, it can save you money over time. Replacing a dirty, clogged filter with a new, clean one can lower your air conditioner's energy consumption by 5 to 15 percent, according to the US Department of Energy. And less energy consumed by your AC equals lower utility bills, which is a huge perk in the heat of summer when electricity costs spike for much of the US.

For more, you can also check out this home upgrade that can save you money on AC costs and this comparison between window AC units and portable AC units.