Boiler Replacement in Tiburon & Belvedere, CA
Radiant floors on several levels, an indirect tank for five bathrooms, a Triangle Tube that's out of parts: replacing a boiler here is a design job, not a swap. We size it to the house, pull the permits, and give you a written estimate first.
Pick a time online. We'll confirm your on-site assessment.
Why replacement here is different
Many Tiburon and Belvedere homes have heating systems that grew over time: a radiant slab downstairs, staple-up radiant under a remodeled upper floor, an indirect tank for domestic hot water, and a panel of zone valves nobody has fully mapped in years.
We size from a heat-loss calculation, not the old nameplate
Walls of bay-facing glass lose a lot of heat on a windy night. Old boilers were often oversized; some remodeled homes are now undersized.
Radiant and hot water need different temperatures
Radiant floors want low-temperature water through a mixing valve; the indirect tank and towel warmers want hot. A low-loss header or primary/secondary piping lets one boiler serve both without short-cycling.
Hot water priority matters in a big house
With several showers running, the indirect tank takes priority and the floors wait a few minutes. We set that up deliberately so nobody notices.
Large loads sometimes call for two boilers
A cascade of two smaller wall-hung boilers can modulate down on a mild evening and still cover a cold snap, and if one needs service the house still has heat. We'll say when one boiler is the better answer.
Triangle Tube owners: what to do now
The Triangle Tube Prestige is a common high-efficiency boiler in Marin homes. Two things have changed.
2025 CPSC recall
The U.S. Consumer Product Safety Commission recalled Prestige Solo, Prestige Excellence and Aerco Esteem condensing gas boilers made between December 2011 and April 2019, more than 60,000 units, because delayed ignition or component damage can release carbon monoxide.
No factory support since November 2025
Triangle Tube ceased operations in November 2025. There's no warranty on purchases from November 3, 2025, and spare parts are available only while existing inventory lasts.
Our advice: don't panic, but plan
A Prestige in good condition, serviced every year, with working CO alarms on each level, can keep running. What you don't want is a heat-exchanger or control-board failure in January with no part on any shelf, and a rushed replacement design for a system this complex. A Prestige Excellence also makes your hot water, so replacing it means deciding how hot water gets made going forward. We replace Triangle Tube units with supported brands such as NTI, Lochinvar Knight, Viessmann, IBC and Navien. Read our Triangle Tube shutdown and recall guide.
Signs your system is due for replacement
A Prestige on the recall list, or throwing ignition faults
Usually: recalled ignition components, or aging parts that can't be sourced.
We check the serial number, test combustion and CO, and plan a replacement before a failure forces one.
The same no-heat call every winter
Usually: heat exchanger scaling, a failing control board, repeated sensor faults.
We compare repair costs to date against a replacement with warranty.
Hot water runs out while the floors are calling
Usually: a boiler undersized for the combined load, or hot water priority not set.
We run heat-loss and hot water load calcs, then resize, add indirect capacity or re-pipe for priority.
Boiler cycles on and off every few minutes
Usually: an oversized boiler on a small zone, no low-loss header, poor reset settings.
We right-size the replacement, add a header or buffer, and set outdoor reset.
Uneven radiant rooms, hot near the manifold
Usually: a worn mixing valve, failed actuators, unbalanced loops.
We rebuild or replace manifolds and mixing, and balance each loop.
Green corrosion or rusted pump flanges near the water
Usually: salt air and humidity in a low-lying mechanical space.
We replace corroded parts and upgrade to better-protected components where it makes sense.
Planning a replacement on the peninsula?
Salt air on the flats and the lagoon
Built in the 1960s on some of the last fill permitted in San Francisco Bay; many of its roughly 200 homes have private docks. Boilers often sit in a garage a few feet above the bay.
Homes went up around an engineered lagoon in the 1950s and '60s; many have since been rebuilt, and most back onto the water. Damp salt air works on copper, brass valves and pump flanges faster than inland.
Homes step down the hill toward the cove. We plan vent terminations so exhaust and condensate don't streak down a façade that faces the water.
Up the hill, Belveron is a different story: about 250 ranch homes built in 1950–51 on a level valley floor. These houses are smaller, and a well-sized combi boiler or a compact boiler with a small indirect tank is often the right answer.
Permits: three jurisdictions, one ZIP code
A 94920 address can fall under three building departments. We handle all three.
Boiler replacement needs a mechanical permit. Inspectors check: an RP backflow assembly on the boiler fill (per Marin Water), a floor drain, an expansion tank supported for twice its filled weight, a low-water cutoff, and working smoke and CO alarms.
Permits are required for all maintenance to mechanical systems. Work is limited to 8 a.m.–5 p.m. on weekdays, with no work on city holidays, and most exterior changes (like a new vent location) need Design Review. We plan around that from day one.
Unincorporated Marin County (County Service Area 29), so permits go through the County's Community Development Agency, not Tiburon Town Hall.
Marin Water lists boilers, radiant systems and docks among the hazards that need backflow protection, tested annually ( backflow prevention). Sanitary District No. 5 requires a sewer lateral inspection on sale or on more than $50,000 of work within three years. We don't do lateral work, but we can refer you.
What a Local Plumbing replacement includes
- Heat-loss and hot water load calculation, and a map of every existing zone
- Removal and disposal of the old boiler
- New high-efficiency boiler (or cascade), piped with a low-loss header or primary/secondary
- Mixing valves, manifolds and actuators rebuilt or replaced as needed, plus a purge station
- New ECM circulators
- Gas line sizing and pressure test; venting chosen with salt exposure in mind
- Inspector items: RP backflow, expansion tank, low-water cutoff, relief discharge, seismic support
- Permit, inspection, startup with combustion analysis, outdoor reset and a full walkthrough
Published ranges; every estimate is in writing before work begins. See all boiler pricing.
Triangle Tube Prestige system serving radiant floors and hot water
Boiler serving radiant floors and domestic hot water. Upgrades: manifold rebuild and a new mixing valve.
What our customers say
Rated 5.0 on Google across our San Rafael and Sausalito locations (340+ reviews). A few from heating customers:
“The pump for my radiant heating went out in the middle of winter… Local Plumbing came right away… got the job done that day, on time, on budget and very professional.”Jeff S. · Local Plumbing customer
“Had to replace a failing gas/solar/radiant/domestic do everything 120 gal hot water tank. The job was complicated and a couple plumbers didn't even submit bids. You want Local Plumbing because they know all things radiant.”Naomi K. · Local Plumbing customer
“They helped us with a client that had issues with a defective radiant heat and hot water system. They were extremely kind and professional with our client who was raving about the work they did.”Alana C. · Local Plumbing customer
Gas boilers and the Bay Area rules
Nothing in the Air District's rules forces a working boiler out of a Tiburon or Belvedere home. Rule 9-6 regulates what can be sold and installed. For whole-house gas boilers (the 75,001 to 2 million BTU/hr class), the zero-NOx requirement applies to units manufactured after January 1, 2031 under the rule as adopted in 2023; draft amendments published in July 2026 would push that to 2033, with a Board decision expected in November 2026. A gas boiler installed now can be serviced and run for its full life. An indirect water heater isn't gas-fired, so it isn't affected on its own. Weighing water heater options too? See our Tiburon water heater comparison.
- Licensed C-16 & C-36 contractor(Lic #1091739).
- Rated 5.0 on Google across our San Rafael and Sausalito locations (340+ reviews).
- Hydronic specialists, with a warehouse and training facility just up the road in San Rafael.
- Owner Conor Crawford was named PHCC California's Young Entrepreneur of the Year for 2026.
Tiburon & Belvedere boiler FAQ
How much does boiler replacement cost in Tiburon?
Our published range for a boiler plus indirect water heater is $19,000–$29,000, with pump, manifold and valve upgrades adding $1,200–$4,500. Complex or cascaded systems are quoted individually, in writing.
Can I still get parts for my Triangle Tube boiler?
Only while distributor inventory lasts. Triangle Tube stopped operating in November 2025, and there's no factory warranty on purchases from November 3, 2025. Plan a replacement before a critical part fails.
Is my Triangle Tube Prestige part of the recall?
The 2025 recall covers Prestige Solo, Prestige Excellence and Aerco Esteem boilers made from December 2011 to April 2019. Check your serial number (our Triangle Tube guide explains how) or ask us to check at a service visit.
What should I replace a Triangle Tube Prestige with?
We commonly install NTI, Lochinvar Knight, Viessmann, IBC and Navien. Whether a boiler plus an indirect water heater or a combi is right depends on the home: how many bathrooms, how much radiant, and how the hot water is used. We size it to the house, not to the old nameplate.
Do I need a permit to replace a boiler in Belvedere?
Yes. Belvedere requires permits for all maintenance to mechanical systems. Work is limited to 8 a.m.–5 p.m. on weekdays, excluding city holidays.
Who issues permits in Paradise Cay?
Marin County, not the Town of Tiburon. Paradise Cay is unincorporated.
How long does a boiler replacement take?
Most installs take 1–2 days. Large multi-zone systems and full manifold rebuilds can take longer, and Belvedere's weekday-only hours factor into the schedule.
Will I be forced off a gas boiler?
No. The Air District's rule controls which new boilers can be sold and installed, starting with units manufactured in 2031 (possibly 2033 if the draft amendment passes). A gas boiler installed today can run out its life.
We replace and service boilers in Old Tiburon, Lyford Cove, Belveron, Bel Aire, Paradise Cay, Belvedere Island, Corinthian Island and Belvedere Lagoon. See our Tiburon and Belvedere pages, NTI boilers, and Boilers & Radiant Heating.
Triangle Tube on borrowed time, or a system that can't keep up?
Book an on-site assessment online, or call or text us.
