These are the questions North County homeowners ask us most, answered the way a good technician would explain them at your kitchen table. Rules and rebates change, so the answers below were checked in October 2026 and link to longer guides with sources. If your question isn't here, ask us.
Costs, buying and replacing
How much does it cost to replace an AC in San Diego County?
Published 2026 cost guides for San Diego put a central AC replacement at roughly $6,500 to $12,000 (Provision Air) or $8,000 to $16,000 (Hans Energy Systems). Those are third-party estimates, not our prices. Size, efficiency, ductwork and permits drive the real number. See our AC replacement cost guide.
Should I repair or replace a 15-year-old AC?
It depends on the repair, not just the age. A failed capacitor or contactor on a 15-year-old system is usually worth fixing. A failed compressor, a leaking coil or repeated refrigerant top-ups usually aren't, because you'd be putting real money into a system near the end of its life. Our repair-or-replace guide walks through it.
Is a heat pump worth it in Southern California?
Often, yes. North County winters are mild, with December lows around 41°F in Fallbrook, which is easy work for a modern heat pump, and one unit handles both heating and cooling. Whether it saves money depends on SDG&E electric rates versus your gas or propane cost. Compare them in our heat pump vs furnace guide.
Should I choose an 80% or a 96% efficient furnace?
A 96% furnace turns more fuel into heat and vents through PVC pipe, but costs more and needs a condensate drain. An 80% furnace is simpler and uses a metal flue. With mild winters, an 80% unit can make sense; a 96% unit pays off faster in colder spots or on propane. More on our furnace installation page.
How long does an AC last near the coast compared with inland?
Usually not as long near the ocean. Salt air corrodes outdoor coils and fins, so a condenser in Oceanside or Carlsbad tends to wear out sooner than the same unit in Fallbrook or Temecula. Rinsing the coil and yearly service help slow it down. Our HVAC lifespan guide covers what to expect.
Permits, rules and rebates
Do I need a permit to replace my AC or furnace in Fallbrook?
Yes. Replacing an air conditioner, furnace or heat pump requires a permit. In unincorporated areas such as Fallbrook, Bonsall, Rainbow and De Luz it comes from San Diego County Planning & Development Services. Cities such as Oceanside, Vista and Temecula issue their own. We pull and file it for you. Details in our permits guide.
What is a Title 24 duct test?
It's a duct leakage test that California's energy code requires when you replace an air handler, an outdoor AC or heat pump unit, or an indoor coil. The ducts are sealed and tested, then a third-party rater verifies the result. Since January 1, 2026, that verification runs under the state's Energy Code Compliance (ECC) program. See Title 24 duct testing.
What SEER2 rating is required in California?
A new split central AC under 45,000 BTU must be at least 14.3 SEER2 and 11.7 EER2 (9.8 EER2 if rated 15.2 SEER2 or higher) in California and the rest of the Southwest. Larger split ACs need 13.8 SEER2 and 11.2 EER2. Split heat pumps nationwide need 14.3 SEER2 and 7.5 HSPF2. These DOE minimums have applied since January 1, 2023. More in our SEER2 guide.
Can I still get an R-410A system in 2026? What is R-454B?
Yes, in many cases. New split systems made since January 1, 2025 use A2L refrigerants such as R-454B or R-32. A May 2026 EPA rule removed the deadline for installing older R-410A equipment, so existing stock can still go in, and R-410A systems can still be serviced. Our R-410A guide explains the change.
Are there still rebates or tax credits for a new heat pump in 2026?
Fewer than before. The federal 25C credit ended for equipment placed in service after December 31, 2025. TECH Clean California's single-family incentives have been closed to new reservations since November 2025, and HEEHRA is fully reserved and no longer accepting new reservations. SDG&E still lists some rebates. Programs change; we'll check current eligibility with you. See our rebates guide.
Do I have to switch to a heat pump when I replace my AC or furnace?
No. California's 2025 Energy Code, in effect since January 1, 2026, does not require a heat pump when you replace the AC or furnace in an existing home. A proposed provision that would have pushed heat pumps for AC replacements was dropped. You can replace like for like, as long as the new equipment meets current efficiency rules and passes its permit inspection.
Troubleshooting and maintenance
Why is my AC running but not cooling?
The most common causes are a clogged air filter, a dirty outdoor coil, a tripped breaker or failed capacitor on the outdoor unit, a frozen indoor coil, or low refrigerant from a leak. Change the filter and check the breaker first. If the outdoor fan isn't spinning or you see ice, turn the system off and book an AC repair.
Why is my furnace blowing cold air?
Check the thermostat first: it should be set to Heat, with the fan on Auto rather than On. After that, the usual causes are a dirty flame sensor, a failed igniter, a clogged filter tripping a safety switch, or no gas or propane supply. If you smell gas, leave the house and call from outside. Our furnace troubleshooting guide helps.
How often should I service my AC and furnace?
Once a year for each, or one visit that covers both. In North County, service the AC in spring before the summer heat and the furnace in fall before the first cold nights. Between visits, change or clean the air filter every one to three months, and more often in fire season. See our tune-ups.
How do I keep wildfire smoke out of my house with my HVAC system?
Close windows and doors, set the system to recirculate rather than bring in outside air, and run the fan with the best filter your system can handle, often MERV 13. Check the filter every few days while smoke lingers and replace it when it darkens. Our wildfire smoke guide has the details.
Working with Fallbrook Heating & Air
What areas do you serve?
We're based in Fallbrook and serve North San Diego County, including Bonsall, Rainbow, De Luz, Pala Mesa, Valley Center, Oceanside, Vista, San Marcos, Escondido, Carlsbad and Encinitas, plus Temecula and Murrieta in southwest Riverside County. From our Fallbrook base it's usually 10 to 20 minutes to Fallbrook homes, about 30 minutes to Rainbow and De Luz, and 30 to 45 minutes to most of North County, depending on the time of day and traffic. If your town isn't listed, call (760) 728-8716 and we'll tell you whether we can help. See our service areas.
Do you work on propane furnaces?
Yes. We service, maintain and install natural gas and propane furnaces of all makes and models, and we repair wall and floor furnaces. Many homes in rural Fallbrook, De Luz and Rainbow don't have natural-gas lines and run their furnace on propane, so tell us your fuel type when you book. Read more on our heating repair page.
Are you licensed and insured?
Yes, we're licensed and insured. Fallbrook Heating & Air Conditioning Inc holds California CSLB license C-20 #638959, active since 1992. The CSLB record shows a contractor's bond and workers' compensation insurance on file. Our technicians are factory trained, and every technician passes a criminal background check. You can verify it yourself on the CSLB website, and read more about our family business on our about us page.
Frequently asked questions
How much does it cost to replace an AC in San Diego County?
Published 2026 cost guides for San Diego put a central AC replacement at roughly $6,500 to $12,000, and others at $8,000 to $16,000. Those are third-party estimates, not our prices. Your cost depends on system size, efficiency, ductwork and permit requirements, so we give free estimates on every new or replacement system.
Do I need a permit to replace my AC or furnace in Fallbrook?
Yes. Replacing an air conditioner, furnace or heat pump requires a permit. In unincorporated areas such as Fallbrook, Bonsall, Rainbow and De Luz it comes from San Diego County Planning & Development Services. Cities such as Oceanside, Vista and Temecula issue their own. A licensed contractor normally pulls it for you.
What SEER2 rating is required in California?
In California and the rest of the Southwest region, a new split central AC under 45,000 BTU must be at least 14.3 SEER2 and 11.7 EER2 (9.8 EER2 if rated 15.2 SEER2 or higher). Larger split ACs need 13.8 SEER2 and 11.2 EER2. Split heat pumps nationwide must reach 14.3 SEER2 and 7.5 HSPF2. These DOE minimums have applied since January 1, 2023.
Can I still get an R-410A air conditioner in 2026?
Yes, in many cases. New split systems made since January 1, 2025 use A2L refrigerants such as R-454B or R-32. A May 2026 EPA rule removed the deadline for installing older R-410A equipment, so existing stock can still be installed, and R-410A systems can still be serviced and repaired.
Are there rebates or tax credits for a new heat pump in 2026?
Fewer than before. The federal 25C tax credit ended for equipment placed in service after December 31, 2025. TECH Clean California's single-family incentives have been closed to new reservations since November 2025, and HEEHRA is fully reserved and no longer accepting new reservations. SDG&E still lists some rebates. Programs change, so we check current eligibility with you.
What is a Title 24 duct test?
It is a duct leakage test required by California's energy code when you replace an air handler, an outdoor AC or heat pump unit, or an indoor coil. The ducts are sealed and tested, then a third-party rater verifies the result. Since January 1, 2026 that verification runs under the state's Energy Code Compliance (ECC) program.
How often should I service my AC and furnace?
Once a year for each, or a single visit that covers both. In North County, service the AC in spring before the summer heat and the furnace in fall before the first cold nights. Change or clean the air filter every one to three months in between, more often during fire season.
What areas does Fallbrook Heating & Air serve?
Fallbrook Heating & Air is based in Fallbrook and serves North San Diego County, including Bonsall, Rainbow, De Luz, Pala Mesa, Valley Center, Oceanside, Vista, San Marcos, Escondido, Carlsbad and Encinitas, plus Temecula and Murrieta in southwest Riverside County. If your town isn't listed, call (760) 728-8716 and we'll tell you whether we can help.