Published August 13, 2025 · Updated September 16, 2026
If you are shopping for a new water heater in Scottsdale, you have probably already seen the ads claiming tankless water heaters pay for themselves in savings, give you endless hot water, and make your old tank look like a relic. Some of that is true. Some of it is marketing. And some of it will lead you to spend several thousand dollars on a system that does not actually solve the problem you thought it would.
Zest Plumbing & Drain has been installing both tankless and tank water heaters in Scottsdale homes since 2008. Here is the straight version of what you actually need to know before you decide.
Gas Tankless vs. Electric Tankless: There Is No Real Comparison
Before anything else, let’s settle one thing: when plumbers talk about tankless water heaters, we are talking about gas-powered units. Electric tankless systems exist, but they require a significant electrical upgrade to your panel, draw enormous amounts of current, and often still struggle to keep up with whole-home hot water demand in a larger Arizona home.
Gas tankless water heaters operate at a fundamentally different level. A quality gas tankless unit fires a high-BTU burner, or two, on demand and delivers hot water continuously without the limitations that make electric units frustrating in real-world conditions. If someone asks you about going tankless and starts talking about electric units, that is worth a longer conversation before you commit.
Everything below refers to gas tankless water heaters.
Which Scottsdale Homeowners Actually Benefit From Tankless
Gas tankless water heaters genuinely shine in specific situations. Here is who makes the most of what a tankless unit offers:
Larger Homes and High-Demand Households
The strongest case for tankless is a home of 2,500 square feet or more with three or more bathrooms, or a household with four or more people living there full time. When multiple people are showering, running the dishwasher, and doing laundry in overlapping windows, a tank water heater is constantly working to recover. A properly sized tankless unit fires continuously and never runs out.
Families With Seasonal High Demand
We install a lot of tankless units for homeowners who describe this scenario: two people live in the house most of the year, but the holidays bring in kids, grandkids, and guests who all need to get ready at the same time before heading out somewhere. A 50-gallon tank that handles two people fine in October hits a wall in December. Tankless handles the surge without any thought.
Short-Term Rentals
If you run an Airbnb, VRBO, or any kind of short-term rental in Scottsdale, tankless makes a lot of practical sense. Guest groups are unpredictable in how many people are showering and when. Hot water complaints generate bad reviews. A tankless unit removes that variable entirely.
When a Standard Tank Is Probably the Better Choice
For a household of two people in a home with two bathrooms, a quality 50-gallon tank water heater does the job well, costs less to install, and will serve that home for 10 to 12 years with basic maintenance. Tankless is not a universal upgrade. It is the right tool for the right situation.
The Biggest Misconception About Tankless Water Heaters
This comes up constantly and it is worth addressing directly: a tankless water heater will not give you faster hot water at the tap.
When homeowners say they want instant hot water, what they are describing is a circulation problem, not a volume problem. Hot water takes time to travel from your water heater to the faucet regardless of how the water was heated. In a larger home, that can mean waiting 30 to 60 seconds or more for hot water to arrive at a distant fixture.
A tankless unit does not solve that. What solves it is a recirculation pump. That is a separate system, separate conversation, and separate installation. If someone sells you a tankless water heater and promises you instant hot water without discussing recirculation, they are not giving you the complete picture.
Dedicated Return Loop vs. Comfort System
There are two recirculation approaches and the difference matters. A dedicated return loop runs a separate hot water return line from the farthest fixture back to the water heater. The pump keeps 120-degree water circulating continuously through that loop so hot water is at the tap within seconds of turning it on. This is the best solution available and the one we recommend when a return line is present or can be added during a remodel.
A comfort system takes a different approach by using the cold water line as the return path. It is a simpler installation because it does not require a dedicated return line, which makes it practical for existing homes where running new pipe is not feasible. The tradeoff is that water temperature at the tap tops out around 100 degrees rather than full hot. That is comfortable for washing hands and rinsing dishes, but most people are not going to want to step into the shower immediately. You will still wait a short moment for full hot water to arrive.
Navien’s Built-In Recirculation Pump
This is one of the practical reasons we lean toward Navien for most Scottsdale installs. High-efficiency Navien tankless units come with an integrated recirculation pump built into the unit. It can be configured for either a dedicated return loop or a comfort-style setup using the cold line. That flexibility means Navien accommodates nearly any installation scenario without requiring a separate pump purchase or additional equipment. Whatever your home’s plumbing layout looks like, the system can be set up to work with it.
| Bottom line on instant hot water: if getting hot water faster at the tap is your primary goal, ask about recirculation when you call. It works with both tank and tankless systems and is often the single most impactful upgrade a Scottsdale homeowner can make for daily comfort. |
The Real Story on Energy Savings
Manufacturer marketing often leads with energy savings as the primary reason to go tankless. The savings are real. They are just not dramatic enough to be the main reason you make a purchasing decision.
A quality gas tankless water heater operates at around 95% efficiency. A quality gas tank water heater operates at around 80% efficiency. That 15-point difference is real, but it translates to roughly 15 cents saved for every dollar you spend on water heating. Your actual savings depend on how much hot water your household uses and what you pay for gas.
For most Scottsdale households, the monthly savings from switching to tankless will be noticeable but will not recover the higher installation cost quickly. The real reasons to go tankless are performance and capacity, not the utility bill math.
Scottsdale’s Hard Water Problem and Why It Matters for Tankless
This is the part that does not show up in the manufacturer brochures.
Scottsdale has some of the hardest water in the country. Minerals, primarily calcium and magnesium, are present in high concentrations. In a tank water heater, scale settles to the bottom of the tank. In a tankless unit, scale builds up inside the heat exchanger, the most expensive component in the system.
A tankless water heater running on hard untreated water will degrade faster than one running on conditioned water, even with regular flushing and descaling service. Flushing a tankless unit twice a year is good maintenance practice, but it does not fully compensate for the ongoing mineral exposure.
What We Recommend
If you are seriously considering a tankless water heater in Scottsdale, a water softener should be part of that conversation. Not a descaling filter. Not a salt-free conditioning system. Those products are better than nothing and will reduce mineral buildup to some degree, but they do not actually remove hardness from the water. A properly sized salt-based water softener removes the hardness.
This is not an upsell. It is the honest advice we give every customer who asks. A tankless water heater in Scottsdale without water treatment is a more expensive investment that requires more maintenance and may have a shorter service life than one installed alongside a softener.
Learn more about water softeners for Scottsdale homes on our water softener page.
Which Brands We Install and Why
We are not brand-agnostic. After installing water heaters in Scottsdale homes for nearly two decades, we have formed clear opinions on what holds up and what does not.
Gas Tankless
Navien is our first recommendation for most installs. The reliability is strong, the output is high, and Navien units work with a 1/2-inch gas supply line because of their negative pressure gas control valve. That matters in older homes where upgrading the gas line to 3/4-inch would add cost and complexity to the job. Rinnai is also a solid unit with a long track record. Rheem’s technology has improved meaningfully in recent years and is a reasonable option in certain installations.
Tank Water Heaters
We install Ruud, which is the professional line from Rheem, and Bradford White. Both are commercial-grade products built for longevity. These are not the same units you find at a home improvement store. The difference in construction quality and expected service life is real.
What Does a Tankless Water Heater Cost in Scottsdale?
At Zest Plumbing & Drain, a standard Navien tankless water heater installation runs $6,495, flat rate. That is the number we publish, and it is agreed with you before any work starts.
Across the broader Scottsdale market, gas tankless installations run $5,000 to $10,000 or more. Where you land in that range depends on the unit size, your existing gas line configuration, the complexity of the installation location, who installs it, and whether additional work is needed. Quotes on the low end of the market often reflect a smaller unit, a straightforward installation, or corners being cut somewhere.
For comparison, our standard 40 or 50 gallon tank replacement runs $2,195 for an electric unit and $2,395 for gas, installed. Across the market, Scottsdale tank installs run anywhere from $1,400 to $3,500.
For complete cost breakdowns, see how much a tankless water heater costs in Scottsdale and how much water heater replacement costs in Scottsdale, or visit our water heater installation services page.
Tankless vs. Tank: Side by Side
| Gas Tankless | Quality Tank (Ruud or Bradford White) | |
|---|---|---|
| Installed cost at Zest | $6,495, standard Navien install | $2,195 electric, $2,395 gas, 40 or 50 gallon |
| Hot water supply | Continuous, does not run out | Limited by tank size, recovers between uses |
| Typical repair cost | $350 to $950 | Flush $176, anode rod $347, elements $478, gas control valve from $737 |
| Service life in Scottsdale | 15 to 20 years with softened water and regular maintenance | 10 to 12 years with basic maintenance |
| Hard water needs | Water softener strongly recommended, plus periodic descaling | More forgiving, annual flush recommended |
| Space | Wall mounted, frees up floor space | Needs a floor footprint |
| Best fit | 2,500+ sq ft, 3+ bathrooms, 4+ people, short-term rentals | Two to four person households with standard demand |
So Which One Is Right for Your Scottsdale Home?
Here is a simple way to think about it:
| Go tankless if: Your home is 2,500+ square feet, you have 3+ bathrooms, your household regularly has 4+ people getting ready at overlapping times, or you run a short-term rental. Factor in a water softener if you do not already have one. Stick with a quality tank if: You have a smaller household, a straightforward hot water demand, and want a reliable system at a lower installed cost. A quality 50-gallon Ruud or Bradford White unit will serve a two to four person household well for a decade or more. |
The honest answer is that both are good options in the right situation. The key is matching the equipment to your actual household needs rather than buying into marketing promises that may not reflect your daily reality.
Frequently Asked Questions
How much does a tankless water heater cost in Scottsdale?
A standard Navien tankless installation from Zest Plumbing & Drain runs $6,495 flat-rate, agreed before work starts. Across the Scottsdale market, expect $5,000 to $10,000 or more. Full details on our tankless water heater cost page.
How much does a tank water heater replacement cost in Scottsdale?
At Zest Plumbing & Drain, a 40 or 50 gallon electric tank replacement is $2,195 installed and a gas tank replacement is $2,395 installed. Market-wide, Scottsdale installs run $1,400 to $3,500. Full details on our water heater replacement cost page.
Do I need a water softener with a tankless water heater?
In Scottsdale, we strongly recommend one. Our hard water scales up the heat exchanger, the most expensive part of a tankless unit, and flushing alone does not fully compensate. A salt-based softener removes the hardness and protects the investment.
Will a tankless water heater give me instant hot water at the tap?
No. Time-to-tap is a circulation issue, not a heating issue. A recirculation pump solves it, and it works with both tank and tankless systems. High-efficiency Navien tankless units include one built in.
How long does each type last?
A quality tank unit typically serves a Scottsdale home for 10 to 12 years with basic maintenance. A gas tankless unit can run 15 to 20 years, but in our hard water that lifespan depends on having a softener and keeping up with regular maintenance.
Zest Plumbing & Drain provides upfront pricing with no trip charge on water heater installations throughout Scottsdale and the greater Phoenix metro. If you are not sure which direction makes sense for your home, call us and we will give you a straight answer.
View our tankless water heater services in greater detail on our tankless page.
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