Your water heater tank takes up a third of the garage, your gas bill keeps climbing, and the last time it leaked, you found out the hard way that it had been there since the house was built? That’s usually the moment people call us. Tankless water heater installation in San Jose is what our team handles most days of the week, whether it’s a 1960s bungalow off The Alameda or a new build in Evergreen with an ADU on the back lot. Grab a quote below, or just call — we’ll talk size, price, and timing right on the phone.
We’ve been at this for almost a decade, all across the South Bay. Our techs carry full insurance and pass a background check before we ever hand them a truck key.
Tankless Installation Options for San Jose Properties
Every house is a little different, and we size the job to yours instead of handing you whatever’s on the truck.
Tank-to-Tankless Water Heater Conversion
This is the job we run most. An old 40 or 50-gallon tank comes out. The gas line gets rerouted. Venting gets upgraded if it needs it. A lot of the time, we’ll add a recirculation loop so you’re not waiting thirty seconds for hot water in the far bathroom. One day, usually, but sometimes even less.
New Tankless Water Heater Installation
Building an ADU, redoing a kitchen, or finishing out a garage? We can easily plan the gas line, venting, and water hookups around the actual space instead of squeezing the unit into whatever corner is left.
Replacing an Aging Tankless Unit
A tankless system can run 15 to 20 years, but the heat exchanger and venting components give out sooner than that. Error codes, dropping pressure, hot water that comes and goes… At some point a full tankless water heater replacement costs less than another round of repairs.
Commercial and Multi-Unit Tankless Systems
Downtown apartment buildings, small offices, multi-family properties — a lot of these run on cascading tankless setups, several units chained together so nobody’s mechanical room turns into a warehouse of tanks. We size and stage it so every tenant gets hot water, even during the 7 a.m. rush.
Schedule a Free Estimate of Your Water Heater Project
Fuel type matters here almost as much as sizing does.
Condensing Gas Tankless Water Heaters
These pull extra heat out of the exhaust before it escapes, which gets efficiency above 90%. They cost more to install, but if your household is running two showers and a dishwasher at the same time, the fuel savings show up on the bill pretty quick. Most of our gas tankless water heater installation jobs these days end up as condensing units.
Non-Condensing Gas Tankless Water Heaters
Cheaper to put in, a fine fit for smaller households or a secondary unit somewhere. It is less efficient, and the venting rules are stricter, but not everybody needs top-tier efficiency. A good number of tankless water heaters in San Jose garages are still non-condensing models, and they've held up fine for years with basic maintenance.
Electric Tankless Water Heaters
No gas line, no venting, nothing burning. Electric tankless water heater installation makes sense for smaller uses. But for whole-house electric, we're going to check your panel's amperage before quoting anything, because a lot of older San Jose homes just don't have the capacity yet.
The Steps Behind a Complete Tankless Installation
Home Visit and Sizing
We look at fixture count, peak usage, your gas line or panel capacity, and how venting will run before recommending a unit. Guess on the size and you end up with a lukewarm shower at 7 p.m. when everyone’s home.
Removing the Old Unit
Converting from a tank, we drain it and haul it off. Nothing is left behind, no rusted tank sitting in the corner of the garage for months.
Gas, Water, and Venting Work
Here’s where the license actually matters. Gas lines get run or modified, water lines connected, venting installed to code — not to whatever’s quickest.
Mounting and Connecting the Unit
The unit goes up on the wall, gets wired or piped in, and ties into your existing plumbing.
Testing and Walkthrough
We run it, check every connection for leaks, test the temperature at a few fixtures around the house, and go over the settings with you before we pack up.
San Jose Permits for Tankless Water Heater Installation
Most tankless water heater installation in San Jose jobs need a city permit, especially if gas lines change or venting gets modified. Skip it, and it tends to come back later — usually during a home sale inspection, when it becomes somebody’s problem to fix retroactively. We pull the permit ourselves, get the inspection scheduled, and deal with the city paperwork so that’s one less thing on your plate.
Why San Jose Property Owners Call Fuse Service
Local Knowledge That Actually Helps
We’ve worked enough San Jose neighborhoods to know which ones still have older gas lines that need an upgrade before a tankless unit goes in.
Licensed, Insured, and Trained
Every tankless water heater installer on our team goes through manufacturer training. And it isn’t just paperwork — get the install wrong and the manufacturer won’t honor the warranty, full stop.
Posted on Yelp
Arun S.
Great work. Thanks Igor and thanks Chris for a professional work done. Our Air conditioning system needed work and you were spot on diagnostics and fix .
Posted on Yelp
Eric A.
Quick easy and painless. Not the cheapest, but they do quality work. I had my bathroom drain cleaned out and pipes snaked.
Posted on Yelp
Stephanie W.
We're just about to have our heat pump and new water heater installed, so I can't speak to that experience yet, but I had to say how helpful their sales rep, Jeff, was with all of my questions to get settled into a plan. I'm one of those people who like to know what's going on line by line, and his patience and knowledge was very appreciated!
Posted on Yelp
Nicasio C.
Received professional service from Fuse from the start of the project to the finish. Project completed was AC and furnace replacement to heat pump and air handler.
Posted on Yelp
Nate M.
Great price to value/service ratio. No complaints and would use their service again.
Posted on Yelp
Frank C.
I had a need to replace our 50G gas water heater. Received several quotes from various contractors. Fuse was the most cost-effective proposal. Quote included new Bradford White heater, new expansion tank (did not have one before), new gas supply line to the heater, new drain pan, new Corro-Protec powered anode to prevent corrosion, and city permit. Installation was smooth. Workmanship excellent. Passed inspection with no issues.
Posted on Yelp
Han Wook C.
Henry and Alex did a fantastic job installing our new heat pump system! They worked hard over two days to get everything set up perfectly. They were punctual, professional, respectful of our home, and extremely knowledgeable. The new system is running great. Huge thanks to Henry and Alex for their hard work--I definitely recommend this team for your HVAC needs!
Posted on Yelp
Matt B.
Update: In what I am pretty convinced was a total coincidence, shortly after the heat pump was installed our gas hot water heater stopped working. I couldn't find anything that the installer would have done to cause it since the symptom was that the gas flame would not stay on. I called Fuse to see what they had to say and within a hour two technicians came out to take a look. After a couple hours of troubleshooting they thought it might be the control board. Of note they didn't charge us for their time. The gas HWH was to be replaced by Fuse with a heat pump based HWH so it seemed silly to invest much effort. Unfortunately there wasn't one of their electricians available for a couple of weeks to install the needed sub-panel. On a follow up call to Fuse, I reminded them that we also have an EV charger in the garage that they might be able to temporarily "borrow" the circuit. The next day the team of Ronnie and Alex came out and installed the new HWH using the EV charger's circuit (having to use a public charger was a small price to pay to having hot water). Once again, a professional job with great attention to detail. Last week Zorik the electrician arrived as scheduled to complete the installation. He worked with me on where I would prefer the sub-panel be installed. Within a few hours, our EV charger was back in business. I appreciated that Zorik took the time to review what breakers were moved so that I could update my records. I was confident that the job (and the others) were all were properly compliant with the building codes. Worth noting, the technician from an independent company came out to do the duct work testing (which passed). As he was leaving the subject of Fuse came up. His comment was that they are the best in the Bay Area.
Posted on Yelp
Jahrell H.
Sergei did an excellent job installing our RO system under the sink and he fixed a leak from plumbing under our home. He is an excellent plumber.
Current Tankless Water Heater Offers
Ask your technician which offers apply when you book — they change month to month.
Schedule Tankless Water Heater Installation in San Jose
Tired of babysitting a tank that’s on borrowed time? Fuse Service covers the whole job — sizing, permits, installation, testing — for tankless water heater installation in San Jose homeowners actually trust. Most projects get quoted same-day and finished within 24 to 48 hours.
Difficult to assess the cost without knowing the details. We should consider the unit itself and how much gas or electrical work is planned to be involved.
For most people, yes. They last longer than tank units, take up a fraction of the space, and skip the standby energy loss you get from keeping 40 gallons hot around the clock. Households with heavier hot water use see the payback fastest.
It comes down to peak flow rate — how many fixtures might be running hot water at once — plus your groundwater temperature, which varies by area. We calculate this on-site instead of pulling a number off a generic chart.
In most cases, yes, especially when gas lines change or new venting goes in. We handle the application and get the inspection on the calendar as part of the job.
Usually one day, somewhere around 4 to 8 hours, depending on how much venting and gas line work is involved.
Gas units generally handle higher flow rates, which suits bigger households. Electric needs enough panel capacity, and that sometimes means an upgrade first. We look at your setup before recommending either one.
Often, yes — federal tax credits and sometimes PG&E or local rebates for qualifying high-efficiency units. What’s available shifts throughout the year, so ask your tech what applies right now.
Don't Take Our Word for It — Check Out Our Reviews!
Posted on Yelp
Arun S.
Great work. Thanks Igor and thanks Chris for a professional work done. Our Air conditioning system needed work and you were spot on diagnostics and fix .
Posted on Yelp
Eric A.
Quick easy and painless. Not the cheapest, but they do quality work. I had my bathroom drain cleaned out and pipes snaked.
Posted on Yelp
Stephanie W.
We're just about to have our heat pump and new water heater installed, so I can't speak to that experience yet, but I had to say how helpful their sales rep, Jeff, was with all of my questions to get settled into a plan. I'm one of those people who like to know what's going on line by line, and his patience and knowledge was very appreciated!
Posted on Yelp
Nicasio C.
Received professional service from Fuse from the start of the project to the finish. Project completed was AC and furnace replacement to heat pump and air handler.
Posted on Yelp
Nate M.
Great price to value/service ratio. No complaints and would use their service again.
Posted on Yelp
Frank C.
I had a need to replace our 50G gas water heater. Received several quotes from various contractors. Fuse was the most cost-effective proposal. Quote included new Bradford White heater, new expansion tank (did not have one before), new gas supply line to the heater, new drain pan, new Corro-Protec powered anode to prevent corrosion, and city permit. Installation was smooth. Workmanship excellent. Passed inspection with no issues.
Posted on Yelp
Han Wook C.
Henry and Alex did a fantastic job installing our new heat pump system! They worked hard over two days to get everything set up perfectly. They were punctual, professional, respectful of our home, and extremely knowledgeable. The new system is running great. Huge thanks to Henry and Alex for their hard work--I definitely recommend this team for your HVAC needs!
Posted on Yelp
Matt B.
Update: In what I am pretty convinced was a total coincidence, shortly after the heat pump was installed our gas hot water heater stopped working. I couldn't find anything that the installer would have done to cause it since the symptom was that the gas flame would not stay on. I called Fuse to see what they had to say and within a hour two technicians came out to take a look. After a couple hours of troubleshooting they thought it might be the control board. Of note they didn't charge us for their time. The gas HWH was to be replaced by Fuse with a heat pump based HWH so it seemed silly to invest much effort. Unfortunately there wasn't one of their electricians available for a couple of weeks to install the needed sub-panel. On a follow up call to Fuse, I reminded them that we also have an EV charger in the garage that they might be able to temporarily "borrow" the circuit. The next day the team of Ronnie and Alex came out and installed the new HWH using the EV charger's circuit (having to use a public charger was a small price to pay to having hot water). Once again, a professional job with great attention to detail. Last week Zorik the electrician arrived as scheduled to complete the installation. He worked with me on where I would prefer the sub-panel be installed. Within a few hours, our EV charger was back in business. I appreciated that Zorik took the time to review what breakers were moved so that I could update my records. I was confident that the job (and the others) were all were properly compliant with the building codes. Worth noting, the technician from an independent company came out to do the duct work testing (which passed). As he was leaving the subject of Fuse came up. His comment was that they are the best in the Bay Area.
Posted on Yelp
Jahrell H.
Sergei did an excellent job installing our RO system under the sink and he fixed a leak from plumbing under our home. He is an excellent plumber.
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