How Long Do AC Units Last? When to Replace an Air Conditioner (Updated for 2025)

When investing in a new air conditioner, one of the most common questions among homeowners is, “How long do AC units last?” It’s a reasonable concern, since air conditioners represent a significant purchase for the average household, more so with today’s higher prices and tariffs.

To help you out with your new AC purchase or replacement, we discuss the lifespan of different air conditioners, what affects their longevity, and how to maximize the operational life of your system.

Lifespan of Different AC Units

Air conditioners are not one-size-fits-all. From central AC to ductless mini splits, each type has a unique life expectancy based on usage, design, and maintenance requirements.

1. Central Air Conditioner

• Average lifespan: 12 to 17 years
• Best-case scenario: Up to 20 years with proper care
• Common replacement reason:

• Worn-out compressor
• Refrigerant leak
• Outdated SEER ratings

2. Ductless Mini Split System

• Average lifespan: 15 to 20 years
• Best-case scenario: 25+ years in mild climates
• Common replacement reason:

• Indoor or outdoor units wearing out 
• Newer, more efficient models available

Check out our wide range of ductless mini splits from renowned brands, from single and multi-zone to DIY systems.

3. Window Air Conditioner

• Average lifespan: 8 to 12 years
• Best-case scenario: 15 years with occasional professional cleaning
• Common replacement reason: 

• Motor failure
• Rust damage
• Outdated energy efficiency

See our extensive list of window AC units from trusted manufacturers.

4. Packaged Terminal Air Conditioner (PTAC)

• Average lifespan: 8 to 15 years
• Best-case scenario: 20 years in low-usage settings 
• Common replacement reason: 

• Age
• Lack of parts
• Decreased efficiency

Shop for PTACs, including the latest smart units!

5. Vertical Terminal Air Conditioner (VTAC)

• Average lifespan: 8 to 15 years
• Best-case scenario: Over 20 years in commercial settings with regular maintenance
• Common replacement reason: 

• Age-related inefficiency
• System incompatibility with upgrades

Browse for VTAC units.

4. Portable Air Conditioner

• Average lifespan: 5 to 10 years
• Best-case scenario: 10 years with gentle use and proper ventilation
• Common replacement reason: 

• Inconsistent performance
• Poor cooling
• Internal wear

See our portable AC units, covering both residential and commercial applications.

Factors That Affect AC Lifespan

There are several aspects that can influence whether your unit falls on the shorter or longer end of its expected lifespan:

1. Manufacturer Quality

Higher-end brands often offer more durable components. Some also use industrial-grade materials even for their residential units, giving them the edge when it comes to longevity at the cost of a higher price tag.

Investing in a reputable brand can lead to longer, more reliable service.

2. Quality of Installation

A poor installation can cause operational issues from day one. Improper sizing or refrigerant charge can significantly reduce lifespan. Unless it’s a DIY mini split and you have the proper skills, always hire a qualified technician to do the installation.

3. System Load and Sizing

Oversized or undersized AC systems are prone to short cycling and inefficiency. A properly sized unit that matches the room or home size will age better. Use our handy AC BTU calculator to make sure your AC is properly sized for the space.

4. Climate and Usage

Air conditioners in hot climates tend to be used more often, which leads to faster wear. In contrast, systems in temperate zones typically last longer due to less frequent use.

High indoor humidity can also cause your AC unit to work harder and wear out prematurely.

5. Maintenance Routine

Regular maintenance like cleaning coils, replacing filters, and checking refrigerant levels can dramatically extend an AC unit’s life. We have multiple AC maintenance guides to help you out:

• Air Conditioner Cleaning & Maintenance
• How to Clean & Change Your AC Filter
• Mini Split Cleaning & Maintenance

6. Air Quality and Environment

Dusty or coastal environments can reduce lifespan. Salt from ocean air, for example, corrodes coils and metal parts quickly. If you live near the coast, make sure you get a unit that is rated for coastal locations.

⚠️ Signs Your AC Unit Needs Replacement

There are common air conditioner problems that can be fixed, and there are issues simply caused by age. If your air conditioner is more than 10 years old, it’s important to watch for signs that it might be nearing retirement. Here are some common red flags:

• Frequent repairs or increasing service calls
• Higher utility bills despite similar usage
• Inconsistent cooling or temperature imbalances that can’t be fixed
• Strange noises like grinding, rattling, or hissing that can’t be diagnosed
• Regular refrigerant or water leaks around the unit
• Your AC still uses HFC-based refrigerants like R410-A or even R22. The EPA is phasing them out in lieu of more efficient and less A2L refrigerants.
• Outdated SEER rating, making it less efficient than modern models. The latest units now follow updated CEER and SEER2 standards.

If your unit is 15+ years old and showing one or more of these signs, a replacement may be more cost-effective than continued repairs. The EPA actually recommends replacing the AC after 10 years.

How to Maximize the Lifespan of Your AC Unit

Here are some expert tips to help you get the most out of your air conditioner:

1. Schedule Annual Maintenance

Have a licensed HVAC professional inspect and tune your unit every spring, just before the warm season. This can catch issues early and ensure good performance for the summer months ahead.

2. Replace Air Filters Regularly

Dirty filters restrict airflow and strain your system. Clean or replace filters every 1 to 3 months depending on usage frequency and home air quality.

3. Clean the Coils

Dirty evaporator or condenser coils reduce efficiency. Schedule periodic coil cleaning, especially if you live in a dusty or coastal area. Check out our coil cleaning products.

4. Use a Programmable Thermostat

Smart thermostats help reduce unnecessary operation, easing wear and improving energy efficiency.

5. Seal and Insulate Your Home

A well-insulated home reduces the burden on your AC. Ensure windows, ducts, and attics are properly sealed. See our guide to Insulation Installation.

6. Shade the Outdoor Unit

Keep your condenser out of direct sunlight when possible. A shaded unit performs better and lasts longer.

When to Repair vs. Replace

If you’re facing costly repairs, consider the $5,000 rule:

Multiply the age of your AC unit by the repair cost. If the number exceeds $5,000, replacement is usually the smarter choice.

For example, a 10-year-old unit with a $600 repair = $6,000 — replacement might be a better long-term decision.

Planning Ahead: When to Shop for a New AC

The best time to start shopping for a new AC is before your old one fails completely. If your unit is more than 12 years old and struggling, consider browsing the latest high-efficiency air conditioners. Not only will your household enjoy better performance and comfort, you will achieve significant utility savings in the long run.

Have questions about how long your current unit might last — or need help finding a new one? Contact us anytime, we’ll be glad to help!