Boiler
Modern high-efficiency, condensing, and non-condensing boilers.
Older hydronic systems for residential and commercial properties across the Bay Area.
Services We Provide
Boiler Diagnostics & Repair
We troubleshoot ignition, circulator, control, combustion, and pressure faults on modern and legacy equipment.
Boiler Replacement
We replace aging cast-iron, atmospheric, and failed condensing units with properly sized, code-compliant equipment.
Legacy System Service
We service older non-condensing and hydronic heating systems, including atmospheric boilers, vintage cast-iron equipment, outdated controls, and aging components.
Upgrades & Maintenance
Annual service plus targeted upgrades to pumps, controls, expansion tanks, and near-boiler piping.
Ready to schedule boiler?
Talk to a specialist today. We respond the same business day with a clear scope and timeline.
Authorized Navien Boiler Service
Diagnostics, maintenance, flushing, warranty assistance, and hydronic integration on NHB, NFB, and NCB systems — including older Navien generations still running across the Bay Area.
Boiler & Hydronic System Expertise
Boiler Diagnostics & Repair
We troubleshoot complete hydronic systems — not just the boiler itself. Our process includes combustion analysis, flow and pressure diagnostics, circulator evaluation, expansion tank checks, temperature differential testing, and control verification to identify the real cause of system problems.
Diagnostics use calibrated gas analyzers, manometers, and clamp meters — combustion CO/O₂, manifold and inlet pressure, flame-signal microamps, ΔT across supply and return, and full fault-code interpretation against manufacturer service literature. Heat-exchanger condition, ignition control boards, and venting integrity are evaluated before any parts are quoted.
Boiler Replacement
We design and install single-boiler and multi-boiler cascade replacements for residential and light commercial applications. Our team helps customers modernize outdated mechanical systems with properly sized equipment, advanced controls, zoning upgrades, and efficient hydronic layouts.
Sizing is driven by Manual J and measured heat-loss data — not appliance swap-out — with near-boiler piping rebuilt for primary-secondary or low-loss header configurations. Stainless or PVC venting, condensate neutralization, outdoor-reset controls, and zoning hardware are specified to match the building and commissioned with a written start-up report.
Legacy System Service
Our engineers work with both modern high-efficiency condensing boilers and older hydronic heating systems, including cast-iron and atmospheric equipment still operating throughout the Bay Area. We diagnose, repair, modernize, and integrate systems that many contractors refuse to service.
Service covers atmospheric draft verification, spillage and CO testing, gas-valve and pilot-assembly rebuilds, refractory inspection, and circulator and expansion-tank replacement on cast-iron and steel-tube equipment. Legacy controls are repaired in place or replaced with modern relays and aquastats so existing systems run safely for another decade.
Upgrades & Maintenance
Our team brings extensive European hydronic experience to ongoing service work — circulator upgrades, control tune-ups, mixing-assembly retrofits, and annual maintenance that keeps the entire loop balanced. This background helps us approach upgrades and maintenance with a deeper engineering perspective.
Annual service includes combustion analysis, flow and ΔT verification, ECM circulator and expansion-tank checks, glycol and water-chemistry testing, and outdoor-reset curve tuning. Targeted upgrades — high-efficiency pumps, modern zone controls, mixing assemblies, and air/dirt separators — measurably extend equipment life and protect rated efficiency.
Thinking about boiler?
Get a fixed-price proposal from a licensed specialist. Same-day response.
Why this is worth doing right.
Repair when sensible
An honest evaluation of repair versus replacement — not a default sales pitch for new equipment.
Quiet, even comfort
Hydronic heat is silent, even, and dust-free when the entire loop is balanced and the controls are tuned.
Longevity
Correct piping, water quality, and combustion setup separate a 7-year boiler from a 20-year boiler.
Safety
Combustion, venting, and gas work are life-safety systems. We test, document, and commission every install.
Manufacturers We Service
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How a boiler project runs.
- 01Evaluate
We assess existing equipment, loads, venting, electrical, and site constraints on-site.
- 02Design
We size and specify equipment to the building — with options and trade-offs explained plainly.
- 03Install
A dedicated lead tech handles a permitted, clean install with finish-grade workmanship.
- 04Commission
We start up, balance, and verify the system against design intent with calibrated instruments.
- 05Support
We walk you through operation, file rebates, and stand behind the system long-term.
Boiler: frequently asked
Trusted Across the Bay Area
Homeowners and businesses across the Bay Area trust ABC Service for hydronic heating, HVAC, boilers, heat pumps, and electrical work.
Extremely clean boiler installation and excellent communication throughout. They engineered the system properly instead of just swapping a unit on the wall.
Fast response and genuinely knowledgeable about radiant heating. Heat pump retrofit and panel upgrade done in one project — permits and rebates included.
Professional team, clean work, and honest diagnostics. Upsized our service for the EV charger — on time, on budget, and inspected the same week.
Tankless install with recirculation done right. Coordinated cleanly with our GC and walked us through every decision. Easily the most professional trade we worked with.
Radiant floors throughout a remodel. They designed the manifold layout properly and the comfort is incredible. Quietest system we've ever had.
Furnace replacement plus new ductwork. Quiet, efficient, and the crew treated our house better than we would have. Inspection passed first try.
Honest diagnostics and skilled HVAC technicians. They took the time to walk through the system and explain every recommendation.
Engineered for the Bay Area
From the Peninsula to the South Bay, San Francisco, and the Santa Cruz coast — we design, install, and service premium mechanical and electrical systems across six counties. Our team supports high-efficiency boilers, hydronic heating, HVAC, heat pumps, and electrical upgrades for modern Bay Area homes and light commercial properties.
- Santa Clara County
- San Mateo County
- San Francisco County
- Santa Cruz County
- Contra Costa County
- Alameda County
* Additional service areas available upon request.
