how long can you run ac without filter

How Long Can You Run AC Without a Filter?

Maintaining a healthy HVAC system is crucial to keeping your home interiors comfortable. However, these complex systems require routine maintenance and upkeep to function optimally. 

Consider changing air filters a necessary step to keep your HVAC system functioning healthily. But what if you don’t have a new filter and need your air conditioner to continue running? How long can you run AC without a filter?

While it’s possible to run your AC system safely for up to eight hours without a filter, hiring Oro Valley’s HVAC services to replace your filters quickly offers the perfect solution. Understanding why air filters are necessary for a healthy system can avoid costly repairs and replacements.

How Air Filters Function in an AC System

Air conditioning systems recycle air throughout your home to provide climate control. Return air vents suck in your interior air, bringing it back into the AC system, where it cools and redistributes it through supply air vents.

Within the return air vents are air filters. As these vents bring air into your AC unit, the filter actively cleans out dirt, mold spores, debris, and bacteria that might not be visible. Especially for homes with children and pets, these filters eliminate quantities of contaminants from the air.

How AC Filters Benefit Your HVAC System

Your HVAC system benefits significantly from air filters. If unfiltered air blows through your system for too long, dust and debris can accumulate on the mechanisms of your AC unit. These contaminants can cause breakdowns that become expensive to resolve.

The Dangers of Running AC Without a Filter

Answering the question “how long can you run AC without a filter” is impossible without exploring the consequences of overrunning your system this way. Below we list some of the top concerns.

Degrading Air Quality

A lack of a filter decreases your home’s air quality considerably. While allowing small amounts of dust and bacteria to recycle through your home’s air may not seem awful, these contaminants can cause adverse respiratory and asthmatic effects. 

Running your AC without a filter too long could increase your chances of sickness. Dirty air can also damage your compressor, another costly system component.

Frozen Evaporator Coils

Dust and debris that flow through an unfiltered AC system will likely settle in the evaporator coils. These coils are responsible for combining refrigerant with the warm air drawn in from your home. 

If evaporator coils become too dirty, they’ll work harder to compensate. However, the additional workload combined with refrigerant attaching to dust particles could freeze your coils. Frozen coils also lead to costly repairs.

Decreased Efficiency and Increased Utility Bills

Dirty air will decrease your AC unit’s efficiency as it works harder to reach desired temperatures. A less efficient system will usually result in increased utility bills. 

Air Conditioning Repair and Maintenance Services From Eazy Breezy Heating and Cooling

For more answers to the question “how long can you run AC without a filter” or to learn about the signs it’s time to replace your air conditioner, call (520) 207-0334 and schedule a service consultation with Eazy Breezing Heating and Cooling today!

Contact Us

Eazy Breezy Heating and Cooling can provide you with regular tune-ups for both your furnace and air conditioner in your Tucson home. We’re professionals, so we’ll always provide you with the best service possible. Don’t wait another day before getting the routine maintenance you need–call us today!

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3710 S Park Ave #705
Tucson, AZ 85713

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