HVAC Repair & Installation in the North Bay
Need Reliable HVAC Services in Marin, Sonoma & Napa County?
Is your air conditioner or furnace acting up? Are you looking to upgrade your heating, ventilation, and air conditioning (HVAC) system?
From fast and reliable air conditioning and furnace repairs to complete system installations, Ongaro & Sons delivers high-quality service with every visit. Our licensed technicians work with top HVAC brands and cutting-edge equipment to ensure your system runs efficiently and reliably.
We understand that your home is your sanctuary. That’s why we treat every project with care, precision, and respect, always prioritizing your comfort and safety. No matter the size of the job, you can trust us to show up on time, explain your options clearly, and get the work done right.
HVAC Services Throughout Marin, Sonoma & Napa County
Ongaro & Sons can help with all your HVAC services throughout Marin, Sonoma, and Napa counties, as well as all surrounding the North Bay communities. Whether you need an air conditioning tune-up or electric heat pump repair, our licensed technicians will recommend the best solutions to keep your family safe and comfortable year-round.
We offer convenient financing options to improve the comfort in your home. Our team will also inform you about available federal and local HVAC tax credits and rebates to make your purchase even more affordable!
Call today at 415-741-2820 for expert HVAC services.
Marin, Sonoma & Napa County Heating and Air Conditioning Repairs
Our licensed technicians arrive in a company vehicle filled with parts, allowing us to address any HVAC repair promptly and professionally. We service and repair all major brands.
Why is my HVAC system making strange noises?
Those odd noises could be clues that something is wrong with your equipment. It could be anything from a loose part to a clogged air filter. Our Ongaro & Sons repair experts can fix minor issues before they turn into costly problems.
Should I repair or replace my equipment?
Repair your HVAC equipment if it is brand new or only a few years old. An exception to this rule is if the repair cost is too high, such as a cracked heat exchanger that is no longer under warranty. It may make more sense to purchase a new system, particularly if you want to upgrade your equipment.
At Ongaro & Sons, we guarantee our repair work with a warranty. Contact us today to fix your HVAC system.
How much does a new HVAC system cost?
The price is determined by the size of the unit and the features. A variable-speed furnace, for example, costs more up-front but uses less energy to operate. You can trust Ongaro & Sons to provide transparent pricing and quotes so you are educated and comfortable with any purchase decision you make.
When should I replace my HVAC system?
Well-maintained HVAC equipment can operate efficiently for 15 to 20 years before parts wear down and struggle to keep up. Are your energy bills increasing every year? Are your repair calls more frequent? New equipment reduces your carbon footprint and provides peace of mind.
HVAC Maintenance Services Throughout Marin, Sonoma & Napa County
Ongaro & Sons can tune up and restore your heating and cooling equipment so you can enjoy it for years to come. We recommend a furnace tune-up in the early fall and an air conditioning tune-up in the spring.
How often do I need to maintain my HVAC equipment?
Routine maintenance keeps your warranty valid. Maintenance also keeps your HVAC equipment running as efficiently as possible, lowering your energy bills. It’s like changing the oil in your vehicle.
What are the benefits of professional HVAC maintenance?
If problems occur, one of our Ongaro & Sons professionals can diagnose and resolve them right away! According to the Department of Energy, regularly scheduled HVAC maintenance visits could reduce your energy expenses. Maintenance will practically pay for itself!
Our Full Range of Heating & Cooling Services
10 servicesYour Comfort, Our Priority
Ongaro & Sons is your trusted heating, cooling, plumbing, electrical, and solar expert, specializing in reliable maintenance and repair services that keep your home running efficiently year-round.
Our certified technicians deliver unmatched expertise with fast, friendly service across Marin, Sonoma and Napa County. From HVAC tune-ups to plumbing repairs and electrical upgrades or solar solutions, we focus on energy-efficient performance and long-term comfort. Count on us to maintain the systems that power your home and keep your environment just the way you like it.
Licensed, Insured, Background-Checked
Our technicians are licensed, experienced, and trained to service all makes and models.
Locally Owned and Operated
Serving the Napa, Marin, and Sonoma communities with personalized, hometown service.
Reliable Repairs
We respond quickly and get the job done right the first time, with no surprises.
Since 1932
Why Ongaro & Sons for Heating and Cooling
Four trades under one roof, and the HVAC side has the manufacturer credentials to prove it.
Schedule Service →Both top manufacturer tiers, not just one
Ongaro & Sons holds Mitsubishi Diamond Contractor Elite status and the Trane Comfort Specialist designation. Both are the highest tier each manufacturer awards, and that standing shapes registration, parts access and extended warranty terms.
We size the system to the house, not the old label
Replacement starts with a load calculation and a look at the distribution, not with matching the tonnage on the unit being removed. Oversizing is the most common reason a new system short-cycles and never feels comfortable.
The ductwork gets tested before equipment is quoted
In North Bay houses with attic or crawlspace runs, leakage regularly costs more capacity than the difference between two efficiency ratings. We measure it first, because sealing frequently buys more comfort than a bigger machine.
Permits pulled and inspections handled
Changeouts in Marin, Sonoma and Napa require permits and Title 24 documentation. We pull them and meet the inspector, so the work is on record when you sell.
A C-20 licensed contractor since 1932
Ongaro & Sons has held an active California contractors licence since 1963 and has been family-owned and operated in the North Bay since 1932. Diamond Certified since October 2016, BBB Accredited with an A+ rating since December 1995.
Discount
Membership
Ongaro Maintenance Plans
Annual maintenance on your home systems provides safeguards and comfort to you and your family. Members get priority scheduling, discounts, and proactive checkups that catch problems early.
Member Discounts
5% off every repair and replacement, all year long.
Peace of Mind
Proactive checkups catch issues before they become big problems.
Courtesy Reminders
We call you to schedule: never miss a seasonal service.
Special Offers
Enjoy our seasonal promotions and save on your next service. Limited-time offers, don’t miss out!
From the Blog
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Unpermitted work creates insurance risk and sale complications in Marin, Sonoma and Napa County. What permits protect and how to verify your contractor.
Read MoreFrequently Asked Questions
Can dirty air ducts affect indoor air quality?
Yes, dust, allergens, mold spores, and other contaminants can accumulate in your ductwork and circulate through your home. Regular duct cleaning helps improve air quality, reduce allergy symptoms, and support a healthier home environment.
How often should air ducts be cleaned?
Air ducts should be professionally cleaned every 3 years, or more often if you notice excessive dust, musty odors, mold growth, or worsening allergies. Homes with pets or recent renovations may need more frequent cleanings.
Is indoor air quality worse in the winter?
Yes, reduced ventilation in California’s colder months (to keep a house warm) traps pollutants inside. That’s why it’s smart to schedule an IAQ checkup from Ongaro & Sons.
What else can I do to remove pollutants in my home?
Preventative maintenance plays a vital role in the performance of all your heating and cooling equipment . Change or clean air filters according to the manufacturer’s directions. Seal leaks in your ductwork . Vacuum and dust regularly. Drain dehumidifiers daily and clean the reservoir. Clean equipment drip pans regularly. Invest in indoor plants.
What impacts indoor air quality?
Everything from dust to humidity and even your HVAC system can affect the indoor air quality in your home. Pollutants can come from a variety of sources, including: Dust, pet dander, and pollen Mold and mildew Household cleaning products Tobacco smoke Poor ventilation Combustion appliances (gas stoves, furnaces) Dirty air ducts or clogged filters
What indoor air quality services do you offer?
We offer indoor air quality testing, IAQ product installation, and duct cleaning. From installing air scrubbers, humidifiers, dehumidifiers, and whole-home filtration systems to providing HEPA air filter subscriptions, we have the tools and expertise to improve the air in your home.
Why is my home dustier than usual? Could it be my HVAC system?
Dust buildup can often be attributed to dirty filters, leaks in ductwork, or dust within your HVAC system. Regular filter changes and professional cleaning can help reduce indoor dust.
Are ductless mini splits a good option for older homes?
Absolutely. Ductless mini splits are ideal for older homes without existing ductwork or when you want to avoid an invasive installation. They offer an efficient, non-invasive heating and cooling solution without the need for major renovations or structural changes.
Can a ductless mini split heat and cool my home?
Yes, a multi-zone ductless system can heat and cool an entire home. Multiple indoor units can be connected to a single outdoor unit, allowing for customized climate control in each room without the need for ductwork.
Do ductless mini splits require regular maintenance?
Yes, regular maintenance is essential to keep ductless mini splits running efficiently. Homeowners should clean ductless filters monthly and schedule professional service annually to check refrigerant levels, clean coils, and inspect electrical components. Schedule your ductless mini split tune-up with Ongaro & Sons.
How can I improve my air conditioner’s efficiency?
Tips to save on cooling costs this summer: Change air filters regularly Use a programmable or smart thermostat Keep blinds or curtains closed during the day Seal air leaks around doors and windows Improve insulation in the attic and/or crawlspace Schedule regular AC service and tune-ups Replace old units with an energy-efficient model
How often should I maintain my AC/cooling equipment?
Regular maintenance is crucial to keep your system running efficiently and to maintain your warranty. It’s akin to regular oil changes for a vehicle. Your air conditioner or air handler should be inspected and maintained annually. Your heat pump should be inspected biannually, once in the spring and again in the fall.