Tankless water heater installation for San Jose homes
Tankless is the work this company is named for: sizing, gas, venting, condensate and the permit, done as one job.
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- Phelan Ave San Jose office
- Tank, tankless, heat pump
Perfect Tankless Plumbing, San Jose, CA
A tankless water heater installation in San Jose usually takes one to two days because the gas line is upsized, new venting and a condensate drain are run, and the city permit is inspected; published 2026 figures put Bay Area tankless installs at roughly $4,500 to $9,500.
Updated September 2026
Water Heaters
What goes into a proper tankless install
A tankless heater fires only when a tap opens and heats water as it flows, so it never runs out. That performance depends on the unit being sized to your peak demand and on a gas supply large enough to feed a burner that can exceed 190,000 BTU. Most houses built for a 40,000 BTU tank do not have that supply.
So a tank-to-tankless conversion is mostly infrastructure: a larger gas line from the meter, stainless or PVC venting depending on the model, a condensate drain with neutralizer on condensing units, isolation valves for flushing, and a wall mount where the tank used to stand.
Cost factors
What a tankless install costs in the Bay Area
Two published ranges are below; the gas line and venting route decide where your install lands.
- Tankless water heater install$4,500 to $9,500 (Bay Area, tankless). Planning range from nextlevelplumbingservices.com, not our quote.
- Tankless water heater services (San Jose)typical $2,096 to $4,993, average about $3,009, low to high $1,000 to $6,000. Planning range from servicemagic.com, not our quote.
- Gas line upsizing. length and size of the new run from the meter
- Venting. PVC for condensing, stainless for non-condensing
- Unit capacity. sized to simultaneous fixtures
- Condensate drain. with neutralizer on condensing units
- Location change. moving from a closet to a garage wall or exterior
- Permit and inspection. required on every replacement
Options
Tankless compared with a new tank
| Gas tankless | 50 gallon gas tank | |
|---|---|---|
| Hot water | Continuous | Limited to the tank |
| Space | Wall-mounted | Floor footprint |
| Install time | One to two days | About half a day |
| Bay Area installed range | $4,500 to $9,500 | $2,200 to $4,500 |
| Upkeep | Annual descaling | Flushing and anode checks |
| Gas line | Usually upsized | Usually existing |
Included
What a tankless install includes
- Sizing to your fixtures and inlet temperature
- Gas line upsizing and pressure test
- Venting to manufacturer specification
- Condensate drain and neutralizer where required
- Isolation valves for descaling
- City permit and inspection
- Commissioning and flushing instructions
Gas tankless
Gas units are the most common choice for whole-house tankless because they deliver high flow rates year round. We size by the number of fixtures you run at once and the winter inlet temperature, then check the meter capacity and the length of the gas run. Most conversions need the line upsized to three-quarter inch or larger. We pressure test the new gas piping, confirm the meter can carry the combined load with your furnace and range, and document it for the inspector.
Electric tankless
Electric whole-house tankless units draw a lot of current, often needing multiple dedicated circuits and a panel with serious spare capacity. In many San Jose homes that makes them impractical without a service upgrade, so we are honest about it. Where they fit, they avoid venting and gas work entirely. For whole-house electric hot water, a heat pump tank is often the better match, and we will say so plainly rather than sell a unit the panel cannot support without an expensive service upgrade.
Condensing vs non-condensing
Condensing tankless units recover heat from their own exhaust, which raises efficiency and cools the flue gas enough to vent through PVC. They produce acidic condensate that needs a drain and usually a neutralizer. Non-condensing units run hotter exhaust and need stainless steel venting, but no condensate line. The choice affects cost, where the unit can sit, and how the vent exits the house. We walk you through both options with the actual vent routing and drain location in your garage or closet.
Point-of-use units
A small point-of-use tankless heater under a sink or near a distant bathroom delivers hot water in seconds instead of waiting for it to travel from the garage. It suits long homes, additions and single sinks far from the main heater. Most are electric and plug into a dedicated circuit. They supplement rather than replace a whole-house heater, and a recirculation pump is sometimes the better answer, which we compare for you once you describe where the wait for hot water is worst.
Local context
Tankless in San Jose's hard water and permit process
A tank-to-tankless conversion is permitted work like any water heater replacement in California, and it typically runs one to two days because of gas upsizing, new venting and condensate drainage. San Jose Water Company data puts valley-floor groundwater at roughly 11 to 26 grains per gallon, which scales heat exchangers, so we fit isolation valves on every install and recommend a softener upstream or, at the very least, an annual descaling flush to protect the unit.
How the job runs
How a tankless conversion runs
- 1
Size the unit
Fixtures, flow and inlet temperature.
- 2
Check the gas
Meter capacity and run length.
- 3
Pull the permit
City of San Jose plumbing permit.
- 4
Remove the tank
Drain, disconnect and haul away.
- 5
Install
Gas, venting, condensate, isolation valves and mount.
- 6
Commission
Test flow, temperature and combustion, then explain flushing.
FAQ
Tankless Water Heater Installation questions from San Jose homeowners
Usually one to two days, then the city inspection is scheduled separately.
Most conversions do. A tankless burner draws far more gas than a tank, and many existing lines are too small.
Yes, as long as it's sized for the fixtures you run at once.
San Jose's hard water makes an annual descaling flush a good baseline, less often with a softener upstream.
Many models are rated for exterior mounting, which frees garage space and simplifies venting.
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From our guides: Tankless vs Tank Water Heaters in San Jose: Which Fits?, Read the guide on tankless install cost, Heat pump water heaters, explained.
One number, any hour
Plan your tankless conversion
Call and we will size the unit, check your gas line and give you the full scope before anything is installed.
