Services We Provide
Tankless Installation
We install condensing tankless units from Navien, Rinnai, and Noritz — interior or exterior, gas or propane.
Tank-to-Tankless Conversion
We handle full conversions including gas upsizing, venting, condensate, and recirculation.
Tankless Water Heater Repair
Our team handles error-code diagnosis, flame-rod and fan replacement, and control-board service.
Descaling & Service
We perform annual flush, inlet filter service, and burner inspection to protect the heat exchanger.
Authorized Navien Tankless Service
Diagnostics, descaling, maintenance, warranty support, and recirculation troubleshooting on NPE-A2, NPE-S2, and legacy Navien tankless platforms.
Not just new equipment — a system done correctly.
Tankless Installation
ABC Service sizes tankless units to actual fixture demand and incoming groundwater temperature — not the marketing GPM rating on the box. Gas line capacity is verified with a manometer under load, venting is run to manufacturer spec, and combustion is measured with an analyzer at commissioning.
Tank-to-Tankless
Most tank-to-tankless conversions require more than swapping the appliance. We upsize the gas line where the calculation demands it, reroute or add stainless or PVC venting to manufacturer spec, run condensate drainage, and add a recirculation strategy so the homeowner doesn't trade a slow recovery for a long hot-water wait.
Tankless Repair
Our team diagnoses error codes, flame-rod and ignition faults, fan and inducer failures, flow-sensor issues, and control-board problems on the dominant Bay Area brands. We stock common consumable parts so most repairs are completed on the first visit instead of waiting on shipping.
Descaling & Service
Annual descaling with a calibrated pump and proper chemistry preserves heat-exchanger capacity, protects the manufacturer's warranty, and is the single biggest factor in pushing a condensing tankless past the 15-year mark in Bay Area water conditions.
Why this is worth doing right.
Endless hot water
Sized correctly, a tankless never runs out — even with simultaneous showers and a tub fill.
Lower operating cost
Condensing tankless models hit 0.93–0.96 UEF, with no standby losses from a hot tank sitting idle.
Smaller footprint
Wall-mounted units recover floor space in garages and mechanical rooms.
Done-right matters
Most tankless complaints come from undersized gas, bad venting, or no recirculation — all preventable.
Manufacturers We Service
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How a tankless water heater 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.
Why ABC Service
Electrical • HVAC • Plumbing Under One Contractor
Licensed C-10 Electrical, C-20 HVAC, and C-36 Plumbing — one team, one schedule, one point of accountability.
Licensed Bonded & Insured
Fully licensed contractor, bonded, and carrying general liability and workers' comp insurance.
Same-Day Service Availability
Urgent service and safety calls prioritized with same-day diagnosis when scheduling allows.
Residential & Commercial Experience
From kitchen remodels and panel upgrades to tenant improvements and commercial equipment hookups.
Flexible financing options available.
Flexible financing options may be available for qualified customers through GoGreen Financing — HVAC, heat pumps, boilers, water heaters, electrical upgrades, and EV chargers.