Signs It’s Time to Replace Your Old HVAC System Instead of Repairing

Signs It’s Time to Replace Your Old HVAC System Instead of Repairing

HVAC repairs are part of homeownership, especially in Northern California where heating and cooling systems run year-round. But there’s a point where repairs become a cycle, and your system starts costing more than it’s worth.

If your air conditioner or furnace is on its last legs, knowing when to replace instead of repair can save you money, energy, and stress. This guide outlines the most common signs it’s time to stop patching your HVAC system and start planning for a full replacement.

Your HVAC System Is More Than 15 Years Old

The average HVAC system lasts between 12 and 20 years. If yours is 15+ years old, even small repairs might not be worth the investment.

Older units also run less efficiently, especially compared to newer ENERGY STAR models. Even if it’s technically still running, you’re likely paying more each month to keep it going.

Warning signs of an aging system include:

  • Long run times to reach set temperature

  • Uneven heating or cooling

  • Noisy startup or shutdown

  • Yellow or flickering burner flames (in gas furnaces)

In Sonoma and Marin counties, where summers are getting hotter and wildfire season lasts longer, your HVAC system now has more work to do than when it was installed. If your equipment is more than 15 years old, it’s time to start looking at replacement options.

Want to know your system’s expected lifespan? North HVAC Services can inspect and assess your equipment — call (415) 845-6910 to schedule a system evaluation.

You’re Paying for Repairs More Frequently

One repair isn’t a red flag. But when repairs start piling up every season, you’re throwing money at a system that won’t last much longer.

If you’ve had to replace multiple components — like capacitors, blower motors, control boards, and compressors — your system is breaking down piece by piece. That’s usually a sign of end-of-life wear.

Keep track of repair costs over the last two years. If you’re spending more than 25–30% of the cost of a new system, replacement is usually the better investment.

Your Utility Bills Keep Increasing

If your usage hasn’t changed but your energy bills are rising, your HVAC system is likely losing efficiency.

This happens gradually as internal components wear out, motors slow down, and refrigerant levels decline. An older system may need to run longer to achieve the same result, which burns more electricity or gas in the process.

High bills with no obvious cause? That’s often one of the earliest signs your system is nearing the end. Newer systems with higher SEER ratings and variable-speed components can cut your usage by 20–40%.

Your Home Has Uneven Heating Or Cooling

Do some rooms stay cold while others overheat? That could be a sign your HVAC system no longer distributes air properly.

This could be caused by:

  • Weak blower motors

  • Damaged or leaking ductwork

  • Failing thermostats

  • Low refrigerant or improper charge

  • Short cycling due to overheating or pressure issues

If these issues persist even after repairs, it could be that your system simply can’t keep up anymore. Newer systems are designed with advanced airflow balancing, two-stage compressors, and smarter zoning controls.

Your System Uses Banned Or Obsolete Refrigerant

If your AC system was installed before 2010, it may use R-22 refrigerant — also known as Freon. R-22 is no longer produced or imported in the U.S., making it extremely expensive to refill.

If your older system develops a leak, recharging with R-22 could cost hundreds, and that’s if you can find it.

Modern systems use R-410A or other newer blends, which are more efficient and widely available. Replacing a system that uses R-22 is often the only realistic long-term option.

Your HVAC System Is Noisy Or Smells Strange

Grinding, rattling, squealing, or burning smells from your HVAC system aren’t just annoying — they’re warning signs.

Common sources of HVAC noise and odors include:

  • Loose or broken fan blades

  • Motor failure

  • Overheating electrical components

  • Cracked heat exchangers

  • Mold or bacteria buildup in ducts

Sometimes these issues can be repaired. But if they keep returning, or if they involve safety concerns (like a cracked heat exchanger), full replacement is often the safest and most cost-effective move.

You’re Struggling With Indoor Air Quality

An aging HVAC system can’t circulate and clean your indoor air the way it used to. You may notice:

  • Dust building up quickly

  • Increased allergy symptoms

  • Humidity issues

  • Musty or stale air in certain rooms

While duct cleaning or adding filtration can help, if your system’s blower or filtration design is outdated, it may be time to start over with equipment designed for today’s IAQ standards.

Many new systems are built to work with MERV 13 filters, HEPA kits, and advanced humidity controls. North HVAC Services installs high-efficiency systems across Napa and Sonoma that include optional air purification — call (415) 845-6910 for options that protect your home’s air long-term.

You’re Remodeling Or Planning To Sell Your Home

Replacing your HVAC system before a major remodel or home sale can help avoid costly disruptions later. It also increases the home’s resale value and appeal to buyers.

Today’s homebuyers are more aware of energy costs, filtration, smart controls, and indoor comfort. An outdated system can hurt negotiations, especially in higher-end markets like Petaluma, Sebastopol, or San Rafael.

A new, high-efficiency system helps your home stand out and can qualify for rebates from PG&E and BayREN when installed by a qualified contractor.

Your System Lacks Modern Features And Compatibility

New HVAC systems come with features that make life easier, healthier, and more efficient. If your current system isn’t compatible with smart thermostats, zoning, whole-house air purification, or variable-speed operation, that may be the final push you need to upgrade.

Homeowners today expect more from their HVAC system:

  • Quieter operation

  • Wi-Fi remote control

  • Built-in diagnostics

  • Integration with home automation

  • Cleaner, healthier air year-round

Sticking with outdated equipment limits your comfort, flexibility, and energy savings.

Use The Repair vs. Replacement Rule Of Thumb

Still unsure whether it’s time to replace? Try this formula:

Multiply the cost of the repair by the age of the system.

If that number is higher than the cost of a new system, replacement usually makes more sense.

Example:

  • $600 repair × 14 years = $8,400 → likely time to replace

  • $300 repair × 6 years = $1,800 → likely worth repairing

This isn’t a hard rule, but it’s a helpful way to evaluate repair costs in context.

Stop Spending on Repairs and Upgrade With Confidence

An HVAC system that’s constantly breaking, driving up bills, or failing to keep your home comfortable isn’t just frustrating — it’s costing you more every year. Knowing when to stop repairing and start replacing is the key to long-term comfort, safety, and savings.

North HVAC Services helps homeowners throughout Sonoma, Marin, and Napa counties compare replacement options, evaluate equipment life, and secure energy-efficient systems that qualify for rebates. Call (415) 845-6910 to schedule an honest system assessment and explore your options with a technician who knows what works in your neighborhood.

How to Prep Your HVAC System for Wildfire Smoke Season in Northern California

How to Prep Your HVAC System for Wildfire Smoke Season in Northern California

Wildfire season in Northern California brings more than smoke—it brings stress, poor indoor air quality, and nonstop AQI alerts. Homeowners in Sonoma County, Marin, and Napa can’t afford to wait for the next red flag warning to start thinking about filtration, airflow, or indoor comfort. You need your HVAC system to work as a shield, not a liability. And that means preparing it to handle smoke before it arrives.

If you’re not sure whether your system is set up to filter out wildfire smoke, this guide will walk you through every critical step. And if you want expert help, North HVAC Services is standing by at (415) 845-6910 to get your system tuned, sealed, and protected.

Why wildfire smoke is dangerous—even indoors

Wildfire smoke contains PM2.5 particles, which are incredibly small—just 2.5 microns wide or less. These particles are small enough to pass through your lungs and into your bloodstream. That’s what makes them dangerous.

Even inside your home, PM2.5 can linger unless you have a filtration system designed to trap it. People with asthma, allergies, heart conditions, or compromised immune systems are especially sensitive, but smoke affects everyone. It can trigger headaches, dry eyes, coughing, sore throats, and fatigue.

When you spend most of your day indoors, your indoor air quality (IAQ) becomes more important than what’s outside. Your HVAC system should be your first line of defense.

1. Install a filter rated MERV 13 or higher

Standard HVAC filters (often MERV 8 or lower) aren’t designed to stop smoke particles. These filters catch dust and hair—not PM2.5. If you want real protection, your system needs to use a MERV 13 filter or better.

Here’s what to know:

  • MERV 13 captures smoke, bacteria, and fine allergens

  • MERV 14–16 offers even more protection but may reduce airflow

  • HEPA filters remove 99.97% of particles but often require system modifications

Not all systems are designed to handle the airflow resistance from high-efficiency filters. North HVAC Services can test your system’s static pressure and recommend upgrades if needed. Call (415) 845-6910 and ask about MERV 13 filter retrofits or deep media cabinets that improve air quality without stressing your blower motor.

Also, filters need to be replaced far more often during wildfire season. If you live in an area with persistent smoke, you may need to change your filter every 2–4 weeks.

2. Seal up your ductwork

Even if you install the perfect filter, leaky ductwork will pull smoky air from attics, crawlspaces, or garages. That smoke enters the system before it ever reaches the filter, and gets blown into every room of your home.

A full duct inspection can identify leaks, disconnected runs, and crushed sections that need sealing. Proper duct sealing also improves energy efficiency and comfort. Many older homes in Sonoma County have decades-old ducts that have never been professionally sealed.

North HVAC Services offers duct sealing and airflow optimization across the North Bay.

3. Switch your system to recirculate

Many HVAC systems bring in outside air to help with ventilation. But during wildfire smoke events, that’s exactly what you don’t want.

Make sure your system is set to Recirculate so it only uses and filters the air already inside your home. This avoids introducing smoky air into your ductwork.

If your thermostat doesn’t give you this option—or if you suspect your system is pulling in outdoor air by default—this is something North HVAC Services can inspect and correct.

When the air outside looks gray, your system should be filtering—not ventilating.

4. Set your fan to “On” during smoke events

Most thermostats are set to Auto by default. That means your fan only runs when heating or cooling is active.

During heavy smoke days, that’s not enough. Set your fan to “On” so it runs continuously and keeps cycling air through your filter.

This prevents particle buildup and allows for more complete filtration. It also keeps temperatures stable if you’ve sealed your home tightly to keep smoke out.

5. Add purification for extra protection

Filtration is the first layer. But for homes with sensitive occupants or persistent smoke exposure, air purification adds a second layer.

There are two main approaches:

  • Whole-home purification systems: Installed inside your HVAC system, filtering every room

  • Portable HEPA purifiers: Great for bedrooms or individual living areas

Whole-home systems can use HEPA-level filters, electrostatic plates, or UV sterilization to treat air. North HVAC Services can install a purifier that works in tandem with your existing furnace or air handler. Portable units, on the other hand, are ideal for renters or secondary coverage.

6. Create a clean air room

You don’t have to purify your entire home to stay safe. Creating one designated clean room can offer major relief during smoky days.

Tips for building a clean room:

  • Choose a room you can seal (like a bedroom)

  • Close doors, use door sweeps, and apply weatherstripping

  • Run a portable HEPA purifier continuously

  • Turn off any exhaust fans or ventilation

  • Use your central system on Recirculate mode to keep filtering the same air

This strategy works best when your HVAC system and portable purifier are working together. North HVAC Services can help you size a purifier for your space and configure your central system to support it.

7. Watch the AQI every day

Wildfire smoke conditions change fast. You need to be responsive.

Check local AQI levels every morning during smoke season using tools like AirNow or PurpleAir. If levels are above 100, that’s your cue to seal up the house, run the HVAC fan on “On,” and keep your purifier active.

At AQI levels over 150, plan to stay indoors and avoid cooking, vacuuming, or doing anything else that might stir up particles inside.

This is also a good time to check your filter. If it’s discolored or smells smoky, it’s time to swap it out.

8. Avoid common HVAC mistakes during smoke season

Even well-meaning habits can make your indoor air worse when smoke is in the air.

Avoid these mistakes:

  • Leaving windows cracked at night

  • Running kitchen or bathroom exhaust fans all day

  • Using candles, incense, or air fresheners

  • Letting filters go unchanged for months

If you’re unsure whether your current system is helping or hurting, call North HVAC Services at (415) 845-6910. We’ll evaluate your system and make sure everything is working in your favor.

9. Consider long-term upgrades for better air quality

If your current HVAC system can’t handle a MERV 13 filter, has poor airflow, or doesn’t let you control recirculation, you may need to upgrade.

Long-term upgrades worth considering:

  • ECM variable-speed blowers: Maintain airflow even with high-resistance filters

  • Deeper filter cabinets: Accommodate 4–5 inch media filters with less restriction

  • Smart thermostats: Automate Recirculate mode when AQI spikes

  • Whole-home purifiers: Protect every room, not just a single area

  • Energy audits: Identify leaks that let smoke in around doors, attics, and crawlspaces

North HVAC Services provides full-system upgrades, from blower retrofits to complete system replacements, built with wildfire resilience in mind.   Wildfire season isn’t going away. But with the right equipment and preparation, you can keep your indoor air clean, safe, and breathable. Whether it’s sealing your ducts, upgrading your filter, or installing a whole-home purifier, the team at North HVAC Services is ready to help. Call (415) 845-6910 to schedule your system inspection before the next smoke wave arrives.