Furnace Repair & Installation
Furnace Services in Marin, Sonoma & Napa County
Are you thinking about upgrading your furnace but not quite sure where to begin?
We understand. Furnaces are more efficient than ever, with a plethora of features designed to keep you comfortable. They come in different sizes and shapes, some more powerful than others. They also have different price points based on their efficiency ratings.
The thermostat is the brain of your heating, ventilation, and air conditioning (HVAC) system. But it’s the furnace that provides all the muscle, teaming up with your ductwork to send warm air throughout your home.
Always remember, a happy home is a warm one! It would only take a few cold days in a row with no indoor heat for all the pipes in your home to freeze.
What matters most is to pick the right furnace that fits your budget and the size of your home. Our team at Ongaro & Sons has the knowledge and expertise to help you make that choice. We’re a trusted name with decades of experience serving homeowners in Marin, Napa, and Sonoma counties, as well as surrounding areas of the North Bay. Give us a call today, we can schedule a consultation to help with your next home improvement project.
Ask About Our Warranties
At Ongaro & Sons, we're here for you after we install your new furnace. Ask about warranties on both the equipment and labor. We're your partner throughout the life of your HVAC equipment.
Installation Matters
We never rush an installation job. Taking shortcuts can lead to rattling noises, loose parts, poor airflow, and other issues. For optimal performance and longevity, a professional installation is just as important as the quality of the furnace itself.
Know Your BTUs
BTU stands for British Thermal Unit. It's a fundamental unit of measurement for heat energy. The BTU rating is crucial because it tells you how much heating power a furnace has. Matching the BTU output to your home's heating needs is essential for efficiency, comfort, and the lifespan of your furnace. The general rule of thumb for furnace sizing is often cited as 30 to 60 BTUs per square foot of living space.
Sizing Matters
Don't assume your old furnace's size is right for your new one. An oversized furnace will cycle on and off too frequently, leading to inefficient operation, uneven heating, and increased wear and tear. An undersized furnace will struggle to heat your home adequately, especially on the coldest days. Our qualified HVAC professional at Ongaro & Sons will perform a Manual J load calculation that considers factors like your home's square footage, insulation levels, window types, and climate to determine the appropriate BTU output for your new furnace.
Keep Your Furnace Running at Its Best With Routine Maintenance
Want to get the most value from your heating system? A preventative maintenance plan is the key. Regular tune-ups help extend the life of your equipment, improve comfort, and lower energy bills by keeping everything running efficiently.
Our licensed technicians perform a full inspection and tune-up to catch small issues before they become expensive repairs. Maintenance isn’t just smart, it’s essential.
What’s Included in Furnace Maintenance?
- Inspect and clean burner assembly
- Check heat exchanger for cracks or corrosion
- Test and calibrate thermostat settings
- Lubricate moving parts to reduce wear
- Inspect and tighten electrical connections
- Clean or replace air filter
- Test safety controls and ignition system
- Measure airflow and check for blockages
Furnace Repairs
Odd-sounding noises, a spike in energy bills, or constant cycling, these signs indicate a problem with your furnace. Don’t wait for a minor issue to turn into a costly problem. Contact us if you detect a problem with your HVAC system. We promise never to replace a part unless necessary, or if we can demonstrate significant cost savings.
Signs you need furnace repair include:
- Strange noises: Clanking, banging, or squealing sounds often signal mechanical issues like a loose belt, worn bearings, or a failing motor. If your furnace starts sounding unusual, it’s best to have it checked right away.
- Rising energy bills: An unexpected spike in your heating bill could mean your furnace is working harder than it should. Reduced efficiency is often caused by a failing component or dirty filters restricting airflow.
- Uneven heating: If some rooms feel warm while others stay cold, your furnace may not be distributing air properly. This can be due to duct issues, a faulty blower, or a malfunctioning thermostat.
- Frequent cycling: Short cycling, when your furnace turns on and off too often, can signal a range of issues, from thermostat problems to overheating. It strains your system and shortens its lifespan.
- Weak or no airflow: Little to no airflow from your vents may indicate a blockage, motor failure, or issues with the blower fan. Poor airflow makes it harder to heat your home effectively and efficiently.
Furnace Installation or Replacement
Don’t invest in a quality HVAC system and then hire a substandard contractor to install it. You will never enjoy the full benefits of a system installed incorrectly.
At Ongaro & Sons, we specialize in installing equipment the right way. We take our time to ensure everything is measured correctly. Our team will also conduct a thorough energy audit of your home to find additional ways to lower your energy use.
Be sure to ask about our convenient financing options (subject to approved credit) designed to make it easy for you to create your dream home.
How do you choose an efficient furnace? The AFUE (annual fuel utilization efficiency) rating on your furnace indicates how much energy it converts. An energy-efficient furnace with an AFUE rating of 95 can convert 95 percent of the energy it consumes into heat. The higher the AFUE rating, the more money you save on monthly utility bills. Energy-efficient furnaces emit fewer greenhouse gases and make less noise when they operate. If you want to reduce your home’s carbon footprint, the perfect place to start is with your heating and cooling equipment!
Furnaces also run at different speeds. The operating speed you choose will impact your comfort, budget, and indoor air quality.
- Single-stage furnaces have just two settings: on or off. Your furnace switches on and continues to run to reach the desired temperature. Once it reaches the temperature, it turns off. Single-stage furnaces are the most affordable models and easiest to install. However, they are the least efficient and tend to create hot and cold spots in larger homes.
- Two-stage furnaces run at full speed and half speed. This allows your furnace to heat your home more evenly, producing a more consistent temperature from room to room. In addition to producing better heating, the half-speed setting is much quieter.
- Variable-speed furnaces are the gold standard of the heating world. These models adjust their speeds to provide precise comfort. They run longer at slower speeds, improving efficiencies while lowering your energy bills. Because they do not frequently cycle on and off, these systems tend to have fewer breakdowns. Larger homes benefit tremendously from variable-speed furnaces.
Schedule Your Furnace Service
Our entire team at Ongaro & Sons values the trust you place in our company. We proudly serve Sonoma, Marin, and Napa counties, including Novato, Tiburon, Sebastopol, and the neighboring communities in between. Call us now at 415-741-2820 or book your appointment online, we’re here to help you stay warm and worry-free all winter long.
Your 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 Furnaces
Heat that stops on the first cold morning is rarely a surprise once you look at the maintenance history.
Schedule Service →Combustion and safety checked, not just ignition
A furnace that lights is not automatically a furnace that is safe. We check heat exchanger condition, venting and combustion air, because a cracked exchanger and a dirty flame sensor present identically to a homeowner.
Trane Comfort Specialist
Trane's top dealer tier, and the standing that counts when a warranty claim needs documenting.
Right-sized replacement
Most replaced furnaces were oversized when installed. A correctly sized unit runs longer and quieter and holds temperature more evenly, and it costs less to run.
The ducts get inspected at the same time
Replacing the furnace and leaving leaking distribution in place means paying for heat that never reaches the room. We test rather than assume.
Permits pulled, inspection met
Furnace changeouts are permitted work in Marin, Sonoma and Napa. Ongaro & Sons has held an active California contractors licence since 1963 and has been in the North Bay since 1932.
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.
Value That Lasts
With Ongaro & Sons, you’re investing in quality, integrity, and service that stands the test of time. Explore our current promotions and see the difference real value makes for your HVAC, plumbing, and electrical needs.
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Read MoreFrequently Asked Questions
Can a heat pump replace my furnace and air conditioner?
Absolutely. A heat pump can serve as both your heating and cooling system. In colder regions, some homeowners choose to pair a heat pump with a backup furnace in a dual-fuel system for maximum efficiency and comfort.
Can radiant floor heating be added to existing homes?
Yes, especially during remodeling projects. Retrofits are possible with proper planning and flooring type.
How can I make my furnace more efficient?
Schedule yearly maintenance, seal air leaks in ductwork, improve insulation, and consider using a programmable thermostat to save energy and boost comfort.
How frequently should I change my furnace filter?
Replace disposable filters once every month (but no longer than every three months) to keep airflow strong and indoor air clean. If your system uses reusable filters, rinse and dry them monthly for best performance.
How long does radiant floor heating last?
Hydronic radiant systems can last 30–50 years with proper maintenance, while electric systems typically last 20–30 years . These systems are low-maintenance and very durable when professionally installed.
How often should I maintain my heating 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 furnace, boiler, or radiant heat system should be inspected and maintained annually. Your heat pump should be inspected biannually, once in the spring and again in the fall.
Is radiant floor heating compatible with all flooring types?
Most flooring types work well with radiant heating, including tile, stone, laminate, engineered wood, and even some carpets. However, materials with better heat conductivity, like tile or stone, tend to perform best.
Is radiant floor heating energy efficient?
Yes, radiant heat is highly efficient because it eliminates duct losses and maintains consistent temperatures. Hydronic (water-based) systems, in particular, can reduce energy use compared to traditional furnaces or baseboard heating.
What size furnace is right for my home?
The right furnace size depends on details like square footage, insulation quality, and window exposure. A Ongaro & Sons HVAC technician can perform a heat load calculation to pinpoint the ideal size.
Why has my heating bill gone up?
Rising energy bills may be due to thermostat settings, drafty windows, poor insulation, or an outdated heating system. Identifying and fixing these issues can improve efficiency.