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Los Alamitos Service Area
Los Alamitos' Local HVAC Experts
One Season provides AC repair, heating service, and complete system installation across Los Alamitos, Rossmoor, Old Town, and College Park. We are CSLB #1038022 licensed, back every install with a 10-year warranty, and answer our 24/7 line with real people.
Book a Free Estimate Call (949) 590-3296Local & Reliable
Your Neighbors’ HVAC Company. Not a Call Center
When you call One Season, you get a local Orange County technician who is a direct employee, never a subcontractor or an out-of-state call center. We have completed thousands of jobs in OC homes, including many of the mid-century ranch houses that define Los Alamitos and Rossmoor. That experience shows up in faster diagnoses and cleaner installs.
5,500+
HVAC Jobs Completed Across OC
5 Stars
From 300+ Verified Google & Yelp Reviews
Same-Day
Avg. Response to Los Alamitos Homes
Local Knowledge Matters
What We See in Los Alamitos Homes
Los Alamitos and neighboring Rossmoor grew up in the 1950s and 60s, when Cliff May-inspired ranch homes were built for a coastal climate and many went up without air conditioning at all. Retrofitting comfort into these mid-century homes is a specialty of ours. County assessor records show more than 3,300 Los Alamitos area homes built in the 1950s.
1950s-1960s
Rossmoor
Rossmoor's Cliff May ranch homes were famously built for indoor-outdoor living, and many never had central air conditioning installed originally. Retrofitting AC into these low-slung homes takes real planning around limited attic space and original floor furnace or wall heater layouts, and we have done it many times.
Early 1900s-1950s
Old Town Los Alamitos
The city's oldest homes near the original townsite often carry generations of piecemeal HVAC additions: a wall furnace here, a window unit there. Modern ductless mini-split systems are frequently the cleanest way to bring whole-home comfort to these houses without tearing into original construction.
1960s
College Park
These 1960s tract homes typically have compact attics and original duct runs that are now past their design life. Leaky or crushed ducts quietly steal capacity, so we always evaluate the duct system, not just the equipment, before recommending a fix.
1950s-1960s
New Dutch Haven
Like much of Rossmoor, homes in this tract were built when the sea breeze was considered air conditioning enough. As summers have grown hotter, we regularly design right-sized retrofit systems here that respect the original single-story ranch architecture.
Preventing Unexpected Breakdowns
Knowing when your block was built tells us what’s coming, so we fix it before you’re without AC in a 95° week.
What We Do
HVAC Services in Los Alamitos
From emergency repairs to high-efficiency system replacements, we deliver real solutions backed by real warranties.
AC Repair
Fast diagnosis and same-day fixes when your system stops cooling. We carry parts for all major brands.
SCHEDULE REPAIR
AC Installation
Right-sized, high-efficiency replacements backed by a 10-year warranty. We optimize air flow, not just equipment.
GET A FREE QUOTE
Furnace & Heating
Repairs and installs that keep up with cold nights. Ensure your heating is safe and efficient.
SCHEDULE HEATING SERVICE
Maintenance Plans
Twice-yearly tune-ups that head off mid-summer breakdowns. Season Pass Membership includes repair discounts.
VIEW MEMBERSHIP DETAILS
24/7 Emergency Service
A real technician dispatched any hour, any day of the year. When the heat hits, we answer.
CALL EMERGENCY LINENeed Quick HVAC Help?
Book your appointment online instantly or call us directly to get an expert scheduled.
Call (949) 590-3296Every Los Alamitos Neighborhood
We cover the entire 90720 zip code, including Rossmoor, Old Town Los Alamitos, and College Park, with same-day dispatch throughout the Los Alamitos area.
Rossmoor
Old Town Los Alamitos
College Park
New Dutch Haven
Carrier Row
Little Cottonwood Park area
Laurel Park area
Katella corridor
What We Stand For
Our Core Values
Honest Communication
No jargon, no hidden agenda, clear explanations and straight answers.
Zero Upselling
Our technicians are never paid to upsell. You get what your home needs.
Punctuality & Respect
On-time arrival, shoe covers on, and your property treated with care.
Upfront Pricing
You approve a clear, flat-rate cost before any work begins.
Guaranteed Workmanship
10-year parts, 2-year labor, and a 6-month follow-up on installs.
Community First
A local Orange County business, invested in the neighborhoods we serve.
Proven Results
Recent Jobs Around Los Alamitos
Los Alamitos • Full System Install
Richard's complete system replacement, 8 jobs with One Season and counting.
Serving Every Los Alamitos ZIP Code
We cover the entire 90720 zip code, including Rossmoor, Old Town Los Alamitos, and College Park, with same-day dispatch throughout the Los Alamitos area.
90720
Call (949) 590-3296
Quick Dispatch Guarantee
- GPS-tracked technicians routed across South OC
- Fully stocked vehicles, most repairs done first visit
- No dispatch fees with completed repairs
Our technicians are strategically routed across South Orange County, meaning we usually have someone minutes from your door.
Customer Reviews
Hundreds of homeowners across Los Alamitos and Orange County trust One Season for honest, reliable HVAC service.
Our shop is at 7700 Irvine Center Dr in Irvine, only about a 35-minute drive to the heart of Los Alamitos. We can usually get out same-day, next-day at the latest. Summertime we can get booked out quick, so call (949) 590-3296 and get our live schedule availability.
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Very professional and easy to work with. Not only did they have a very good solution for replacing the old furnace and air conditioner, but they also redid much of the ductwork so everything works better. I highly recommend One Season!
David Nale
April 20, 2026Great company that was referred to me in 2024 by a good friend. Used them to install new ductwork, routine system inspection and may continue to use them in the future as needed!
Koley Anthony
January 13, 2026I had a replacement A/C installed today. I would give One Season 6 stars, if I could. They were the best of 6 bidders I had. Aubrey had worked with me tirelessly to find a solution for my very difficult space constrains. He and Mike were also super patient while working out the "legalize" of the contract, which I was insisting on. And finally, they both as well as Josh and Ben have done a superb job replacing a condenser and a coil today. Everything was done meticulously, all my questions answered, every step of the process explained. All 4 were were nice and extremely professional. The work areas and the house front were left clean. I highly recommend this company for anyone's heating or A/C work.
Walter Patton
February 4, 2026 -
The only repair and install service I will use for now on. Quick response and great price. Thank you
Tausha Wagner
February 6, 2026Amazing vendor. Very honest, and have amazing tech. We were in difficult situation where our lennox has proprietary system and our thermstat went out. But he made simple and just easy to be out of that lennox dependency. Will use them again in the future with their annual maintenance
Johny Hartanto
April 21, 2026The company I give five stars. Excellent response and follow through with great communication from their office. The technician I give six stars. Very knowledgeable, fast, friendly and a great communicator advising me on the condition of my equipment and what I might expect going forward.
Dennis Toussieng
March 20, 2026 -
From point of contact through job completion, my experience with One Season was exceptional in every way. The team is very patient and kind, like a friend over for a visit. They are knowledgeable and good communication. The work quality is top notch. The equipment is high quality. I highly recommend using One Season.
Jason Marshall
January 22, 2026I have used many AC companies over my years but none have been as complete in their Preventative Maintance as One Season Heating and Air. They are the only company that I will use Thank You
l g
January 9, 2026Exceptional service, fair pricing, they don’t make you feel like you have to buy stuff you don’t need which makes me feel confident I’m not dealing with someone who just wants my money but instead honest, hardworking people who want to make sure my system runs well and stay within my budget. The techs are knowledgeable and helpful. And again, them being honest is a really huge factor for me. I will always call them for any needs I have for my HVAC services, who doesn’t love their home to feel like one season all year round?!
luisana pinedo
March 19, 2026
CA License #1038022
5 Stars · 300+ Google & Yelp Reviews
10-Year Parts Warranty
100% Satisfaction Guarantee
Good Questions, Straight Answers
How quickly can you reach a home in Los Alamitos or Rossmoor?
We offer same-day service across the 90720 area, and our phone line is answered 24/7 by real people. Call any time and we will get a licensed technician to your door as fast as the schedule allows.
Are you licensed, and do you pull permits for work in Los Alamitos?
Yes. One Season is a licensed California HVAC contractor, CSLB #1038022, and we pull the required permits for system replacements and major installations. Permitted, inspected work protects your home's value and keeps everything up to code.
My Rossmoor home never had central AC. Can you add it?
Yes, this is one of our most common projects in the area. Cliff May-style ranch homes have limited attic space, so we design each retrofit individually, whether that is a compact ducted system, a ductless mini-split setup, or a hybrid. You get honest options, not a one-size-fits-all quote.
What should owners of 1950s-60s homes watch for in their HVAC systems?
Original wall furnaces and floor furnaces from that era are often inefficient and can develop safety issues with age, and any early ductwork is usually leaky by now. We recommend a professional inspection so you know exactly where your system stands before peak season.
Do you offer a maintenance plan?
Yes, our Season Pass maintenance plan includes seasonal tune-ups, priority scheduling, and member benefits. Regular maintenance is especially valuable for the retrofit and mid-century systems common in Los Alamitos and Rossmoor.
Get in Touch
Get Same-Day HVAC Service in Los Alamitos
Call now and talk to a real person, or book online and we’ll confirm your arrival window within minutes.
(949) 590-3296 · 24/7 Emergency Line
7700 Irvine Center Dr #800, Irvine, CA 92618
Book Your Free Estimate
No obligation, flat-rate pricing. We’ll contact you within 15 minutes.
What to Expect from Us
Clear Communication & Honest Advice
Straight answers about what your system needs, and what it doesn't.
Punctual, Respectful Technicians
We show up on time and treat your home like our own.
Upfront Pricing, No Surprises
Flat-rate quotes approved by you before work begins.
Guaranteed Workmanship & Satisfaction
Backed by a 10-year parts and 2-year labor warranty.
