Tankless Water Heater
Tankless Water Heater Services in Marin, Sonoma & Napa County
A tankless water heater trades the storage tank for on-demand heating: water is heated as it moves, so the supply does not run out and the standby losses of a tank disappear. Whether that trade suits a given house depends on gas capacity, venting, water hardness and how hot water is actually used, which is why we treat every tankless job as a sizing exercise first. Ongaro & Sons installs, services and descales tankless systems across Marin, Sonoma and Napa County, and we will tell you plainly when a conventional tank is the better fit.
Tankless Maintenance That Protects the Investment
The heat exchanger is the heart of a tankless unit, and hard water is its enemy. Parts of Marin and Sonoma run hard enough to build measurable scale within a couple of years, which shows up as falling flow, rising error codes and shortened service life. Descaling on an interval matched to your district’s water, replacing inlet screens, and checking condensate runs are the visits that let a twenty-year design life actually deliver it. Every unit we install gets isolation valves, so a flush is quick service rather than a re-plumb.
Enrolling in Ongaro Maintenance Plans makes descaling a scheduled visit instead of a reminder on your list, with member discounts and priority scheduling included.
Tankless Water Heater Repair
The common complaints have knowable causes: water that alternates hot and cold, error codes under heavy demand, flow that has faded over months, or a unit that cannot keep two fixtures happy at once. Some of these are scale, some are gas supply, some are sizing decisions made before we arrived. We diagnose against the whole system rather than swapping parts, and we put the finding in writing with the price before any repair begins.
Installation and Replacement, Sized for Winter Groundwater
A tankless heater that performs in summer can disappoint in winter, when inlet water runs coldest and the temperature rise asked of the unit is greatest. We size against winter conditions and simultaneous fixture demand, confirm the gas line can actually feed the burner, and engineer venting and condensate to code in the same visit. If fast hot water at distant fixtures matters, recirculation is designed into the system rather than added after.
We install, service, and descale tankless systems throughout the North Bay, including Cloverdale, Corte Madera, Mill Valley, Napa, Novato, Petaluma, Rohnert Park, San Rafael, Santa Rosa, Sausalito, Sebastopol, Sonoma, and Windsor.
Schedule Your Tankless Water Heater Service
Whether you need a descaling visit, a repair, or a full tankless installation sized for your home, our licensed team is ready to help across Marin, Sonoma, and Napa counties. Call us at 415-741-2820 or book your appointment online.
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 Tankless Water Heaters
A tankless unit is a small engine on your wall; it repays exactly the care its install put in.
Schedule Service →Installation and Replacement, Sized for Winter Groundwater
A tankless heater that keeps up in July can fall behind in January, when groundwater runs coldest. We size against winter inlet temperatures and the fixtures that actually run together, so the shower stays hot in the month that tests it.
Descaling matched to your water, not a calendar
Parts of Marin and Sonoma run hard enough to scale a heat exchanger measurably within a year or two. We set the descaling interval from your district’s hardness and build isolation valves into every install so the flush is a service call, not a surgery.
Gas, venting and condensate engineered as one job
A tankless conversion usually asks more of the gas line than the old tank did, and condensing units need venting and condensate runs done to the letter. One C-36 crew handles all three, permitted, so nothing is left for a second contractor.
Recirculation designed in, not bolted on
If you want hot water fast at a far bathroom, the recirculation decision belongs in the tankless design, when the loop, controls and heater are chosen together.
The price is agreed before work starts
You see the number before the work begins. Ongaro & Sons has been family-owned in Marin, Sonoma and Napa since 1932 and Diamond Certified since October 2016.
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!
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Read MoreFrequently Asked Questions
Can an RO system remove hard water minerals like calcium and magnesium?
Yes, RO systems reduce hardness-causing minerals, but they’re not a substitute for a whole-home water softener. For households with very hard water, it’s best to combine a water softener with a reverse osmosis system.
Can I install a water filtration system myself?
Basic under-sink units can be DIY, but whole-house systems should be installed by a licensed plumber to ensure proper connections and code compliance.
Can I stay in my home during waterline replacement?
Yes, in most cases, you can remain at home. Water will be shut off temporarily, but professional plumbers coordinate timing to minimize disruption.
Can sediment filtration improve water taste and odor?
Sediment filters are primarily for removing visible particles. To improve taste and odor, they’re often paired with activated carbon filters or reverse osmosis systems, which target chlorine and other chemical contaminants.
Do I need a reverse osmosis system if I already have a water softener?
Yes, softeners remove minerals, while RO systems target smaller impurities and improve taste and purity.
Does my water heater need maintenance?
Yes, flushing once a year removes sediment that can reduce efficiency and damage the tank. Annual inspections can also review the exterior for corrosion or leaks around connections and ensure the pressure is where it should be.
How do I know if I need a water softener?
Signs include soap scum, stiff laundry, cloudy dishes, and frequent scale buildup on faucets and appliances.
How do I know if I need a waterline replacement?
Frequent leaks, reduced water pressure, or discolored water are signs your main water line may need replacement.
How long should a water heater last?
Most conventional water heaters last 8–12 years. Tankless units can last 15–20 years with proper maintenance.
How often does a reverse osmosis system need maintenance?
RO systems require filter changes every 6–12 months, depending on water quality and usage. The RO membrane typically needs to be replaced every 2–3 years. Routine maintenance ensures optimal performance and water quality.
Is reverse osmosis water safe for cooking and drinking?
Yes, RO water is highly purified, making it ideal for drinking, cooking, ice cubes, and even baby formula.
Is sediment filtration necessary if I already have a water softener or RO system?
Yes. Sediment filters are essential even with a softener or reverse osmosis system. They act as a pre-filter, protecting more sensitive systems from clogging or premature wear caused by particulate matter.
What can a water filtration system remove?
It removes contaminants like chlorine, lead, sediment, and other impurities for better taste, odor, and safety.
Where is a reverse osmosis system installed in the home?
Most residential RO systems are installed under the kitchen sink and connected to a dedicated faucet. Whole-house RO systems are also available, though they are typically only used in extremely poor water quality areas.
Why does my water heater take so long to heat up?
Common causes include sediment buildup, a failing heating element, or a long distance between the heater and fixtures. Alternatively, nothing could be wrong, and you just need a recirculating pump to reduce your wait time.