When to Replace Your AC Unit in Las Cruces, New Mexico
Replace your air conditioner if it’s more than ten years old, no longer cooling your home evenly, or requiring frequent repair service.
Here in Las Cruces, where summer temperatures regularly reach triple digits, an aging or inefficient AC unit can quickly lead to rising energy bills and uncomfortable indoor conditions. Mechanical parts wear down over time, refrigerants become outdated, and performance can decline even with regular maintenance.
In this guide, learn when you should replace your air conditioner and the factors, such as age, warranty status, and unit cost, that influence your decision.
If you are unsure about the system’s condition, contact Air Control Services at 575-567-2608. Our Las Cruces, NM, HVAC technicians will inspect your air conditioning unit and suggest whether a targeted repair or full replacement is the most cost-effective option.
Now, let’s take a look at the most common signs it’s time to replace your AC unit.
1. Your Air Conditioner Isn’t Cooling Properly Anymore
If your air conditioner isn’t cooling properly anymore, it may be a sign of a failing compressor, low refrigerant, or restricted airflow.
Weak or warm air from the vents, hot spots around the home, or a system that runs constantly without results often indicate internal wear or declining efficiency.
Check the air filter, thermostat settings, and ensure all vents are open and unobstructed. If these basic steps don’t resolve the issue, the problem is likely inside the unit and requires professional inspection or full replacement.
2. Energy Bills Are Spiking Month After Month
If you’ve noticed your electric bill inching higher every summer, your air conditioner may be the reason. Older systems often lose efficiency over time, especially if coils are worn out or internal components are starting to fail.
Even with regular maintenance, aging units can struggle to cool your home without running longer cycles. That extra runtime drives up energy use and your utility costs. In Las Cruces, where AC systems work overtime for months at a stretch, the difference in efficiency can add up fast.
If you’ve ruled out duct leaks and thermostat issues, but the bills keep rising, an upgrade to a newer, high-efficiency model could reduce monthly costs and improve overall comfort.
3. The Age of Your AC Unit Is Over 10 - 15 Years
If the age of your air conditioner is more than ten to fifteen years, it’s likely nearing the end of its useful lifespan.
Most AC units lose efficiency over time, even with routine maintenance, and older air conditioning systems are more likely to experience part failures, uneven cooling, or high energy use.
While a well-maintained air conditioning unit can sometimes operate beyond its expected life expectancy, many homeowners find that system performance drops off sharply around the ten-year mark.
4. You're Dealing With High Humidity
If you’re dealing with high humidity indoors, even when the AC is running, it may be a sign that your air conditioner is no longer regulating moisture effectively.
Part of a well-functioning air conditioning system’s job is to remove excess humidity from the air while cooling. When that function starts to fail, the indoor air can feel sticky, heavy, or warmer than the thermostat indicates.
High humidity can also lead to other problems, such as condensation around vents, musty odors, and mold growth, especially during extended hot periods like we see in Las Cruces.
5. Repairs Are Getting Too Frequent or Too Expensive
If you’re calling for AC repairs more than once a year or seeing the same part fail again and again, it’s time to take a closer look at the long-term cost. Frequent service calls don’t just mean hassle; they’re a warning sign that your system may be nearing the end of its useful life.
In many cases, homeowners in Las Cruces use the $5,000 rule to decide: multiply the age of the unit by the cost of the repair. If that total is over $5,000, replacing the system is usually the more practical and cost-effective choice.
6. Loud or Strange Noises Are Coming From the Air Conditioning System
If your air conditioner has started making banging, screeching, rattling, or buzzing sounds, it’s a sign that something’s wrong inside the system.
While some noise can be fixed with a minor repair, repeated or worsening sounds often point to internal damage or aging components.
Common causes include:
- Loose or broken fan blades
- Failing motor bearings
- Refrigerant leaks
- Debris in the outdoor condenser unit
- Electrical issues in the compressor
A loud system that is never used to make noise could mean the HVAC unit is wearing down faster than expected. If strange sounds come back shortly after a repair or new noises keep appearing, it may be more cost-effective to replace the air conditioning system rather than keep chasing fixes.
7. Musty Smell Coming From the Vents
If your AC smells like mildew or dirty laundry, you may have mold or bacteria inside the system.
This often means:
- Evaporator coils aren’t draining properly
- The condensate line is clogged
- Moisture is trapped in the ductwork
This smell typically occurs when the AC turns on and can spread airborne mold spores throughout your home. The unpleasant smell can also aggravate allergies, asthma, and other respiratory issues, especially in children and older adults.
If you suspect mold growing inside the unit, try replacing the air filter, flushing the drain line, and having the coils professionally cleaned. If the smell persists, it may be time to consider full AC replacement.
8. Burning or Electrical Smell While Running
If your AC smells like burning plastic, melting wires, or hot electronics, turn it off right away.
This could be caused by:
- An overheating blower motor
- Burnt capacitors or frayed electrical wires
- Dust burning off the heating elements (in dual-purpose HVAC units)
Electrical problems in air conditioners can be a fire hazard. Avoid DIY fixes if you notice burning or an electrical smell and call a licensed HVAC company near you for inspection.
A licensed HVAC technician will check for short circuits, test the capacitor, and replace damaged wires, motor parts, or the control board to keep your system safe. If your unit is older or has repeated electrical failures, an air conditioner replacement may be the safer and more cost-effective option.
9. Leaking or Moisture Around the AC Unit
While a little condensation around your AC unit is normal, visible puddles or dripping water usually indicate problems with a clogged condensate drain, a frozen coil, a cracked drain pan, or even a refrigerant leak.
Left unchecked, that moisture can soak into your walls or flooring and trigger mold growth indoors. If it’s a refrigerant that’s leaking, low levels can harm cooling performance and pose health concerns, depending on the type of refrigerant used.
If you’ve already tried fixing it once or twice and the unit keeps leaking, or you’re seeing rust or water damage at the base, replacement is often the more reliable (and cost-saving) move.
10. AC Uses R-22 Refrigerant (Freon)
If your AC still runs on R-22 refrigerant, commonly known as Freon, it’s officially outdated. The U.S. banned R-22 production in 2020 due to its environmental impact, which means it’s no longer being manufactured or imported.
What does that mean for you? If your unit springs a leak or needs a recharge, getting R-22 is now extremely expensive – if it’s available at all. Many HVAC companies won’t even service older systems with R-22 because of the limited supply and higher risk of failure.
If your system was installed before 2010, there’s a good chance it uses R-22. In that case, replacing the unit ensures your home’s HVAC system can actually be repaired and supported going forward.
11. Your Warranty Has Expired
Once your air conditioner’s warranty runs out, every repair comes out of your pocket – and costs can add up fast. Without coverage, even a simple part upgrade can turn into a pricey surprise, especially on older systems where parts are harder to find.
If your unit’s over 10 years old and no longer under warranty, you’re likely paying more to keep it running than it’s actually worth. Many homeowners in Las Cruces, New Mexico, hit this point and realize a new system with a fresh warranty just makes more financial sense. Plus, newer models tend to be quieter, more efficient, and easier to maintain.
Time for AC Replacement? Call Your Trusted Las Cruces HVAC Contractor
Consider air conditioner replacement if your air conditioner shows any of the above mentioned signs. Putting it off can lead to higher repair costs, safety risks, and uncomfortable indoor conditions.
For honest advice and expert service, contact Air Control Services, your local HVAC company in Las Cruces at 575-567-2608. We’ll assess your current cooling system and help you decide if a targeted repair or a new AC installation is the smarter, more cost-effective choice.
FAQs
How often should you replace your air conditioner?
Most air conditioners last 10 to 15 years with regular maintenance. If your system is over a decade old and starting to need frequent repairs or has poor cooling performance, it may be time to purchase a new one.
Should I replace my 20-year-old air conditioner?
We suggest replacing an AC over 20 years old. Even if it still runs, it likely uses outdated refrigerant, runs inefficiently, and could be costing you more in energy bills and repairs than a new system would.
Should I replace my 30-year-old air conditioner?
A 30-year-old AC system is far past its expected lifespan. Modern air conditioners are much more energy-efficient, quieter, and safer. Holding onto an older unit risks sudden failure and higher monthly costs.
How much do central AC units cost in New Mexico?
The unit cost for replacing a central AC system typically ranges from $4,500 to $9,000. This includes the price of AC units, installation, and possible upgrades. Your actual price will depend on the brand, size, and whether your home needs new ductwork.
How do I choose the right HVAC company for system replacement?
Look for a licensed HVAC company with solid local reviews, transparent pricing, and warranties on both labor and equipment. Always get a detailed quote before agreeing to HVAC replacement service.