Good to Know / Remodeling guide
7 Shocking Facts About Tankless Water Heaters
Model selection: Compare the heater’s output at the required temperature rise, not its maximum advertised flow alone. Check exact model numbers, pump requirements and warranty conditions before ordering.
01 / Introduction
Introduction: Why Tankless Water Heaters Are Gaining, and Losing, Attention
Tankless water heaters, also known as on-demand systems, have exploded in popularity over the last decade. Promising endless hot water, lower energy bills, and sleek space-saving design, these units have become the go-to upgrade in modern homes.
But are they really the future of home water heating, or just an overhyped investment?
At Bezruchuk Inc., we’ve worked with dozens of clients across bathroom remodels, walk-in tub installations, and custom shower conversions. And we’ve seen firsthand how tankless water heaters often fall short of expectations, especially when the fine print is ignored.
In this guide, we’ll walk you through 7 shocking facts you need to know before choosing a tankless system. From real-world performance issues to unexpected maintenance costs, you’ll get the full picture, not just what sales reps want you to hear.
If you’re planning a home remodel, adding a walk-in tub, or upgrading your heating system, read this first to avoid costly mistakes. Then get a free quote to find the right solution for your needs.
Whether you live in Puyallup, Bellevue, or the greater Seattle area, we’ll help you make the smart choice for your next project.
Let’s dive in.
02 / The Real Cost of Tankless Water Heater Systems
The Real Cost of Tankless Water Heater Systems
One of the biggest selling points of a tankless water heater is its energy efficiency. But what many homeowners don’t realize is that the upfront and hidden costs often outweigh the long-term savings.
Let’s break it down: a traditional 50-gallon water heater typically costs around $2,000 to $2,500, fully installed. In contrast, a tankless system often starts at $3,000 just for the unit, and installation can add another $2,000 to $4,000, especially if you need new gas lines, electrical work, or ventilation.
Tankless vs. Traditional: Installation and Unit Cost
| System Type | Unit Cost | Installation Cost | Typical Lifespan |
|---|---|---|---|
| Traditional Tank | $1,200–$2,000 | $800–$1,500 | 10–15 years |
| Tankless System | $2,800–$4,500 | $2,000–$4,000+ | 15–20 years (with maintenance) |
If a heater is offered through a rental or service contract, compare the total payments, ownership terms and maintenance obligations with an outright purchase. Rental arrangements are not universal.
That’s not exactly what we’d call energy savings.
Maintenance Costs Add Up Quickly
Follow the manufacturer’s maintenance schedule and water-quality requirements. Descaling frequency depends on the model, water conditions and use; ask a qualified installer to explain the required service.
And unlike a simple tank replacement, many tankless heaters use proprietary parts that can take weeks to arrive from overseas. That means no hot water and long waits, often with premium service fees.
In comparison, a traditional water heater is straightforward. If it ever fails, replacement is fast, cheap, and reliable.
Want More Hot Water Without the Cost?
Our team often recommends installing a high-efficiency tank system with a recirculation pump. It delivers hot water in seconds, saves energy, and avoids the common issues of tankless systems. See how it works in this project.
Pro Tip: Don’t just compare monthly energy bills. Always include installation, maintenance, and lifespan when evaluating your water heater investment.
Click here to request a free quote and compare smart water heater options for your remodel or new construction project.
03 / Performance, Problems, and When Tankless Systems Fail
Performance, Problems, and When Tankless Systems Fail
Tankless water heaters promise “endless hot water.” But in real-world use, that statement comes with major caveats. These systems can struggle to deliver consistent performance, especially in multi-bathroom homes or when paired with low-flow fixtures.
Many of our remodeling clients report delays, inconsistent water temperatures, or cold surges. These issues aren’t rare, they’re common symptoms of system mismatch, poor installation, or low water pressure.
Low Flow Fixtures = Big Tankless Headaches
Modern plumbing fixtures are designed to conserve water. But when flow rates fall below a tankless system’s minimum threshold, the heater doesn’t even turn on. That means you could be sending cold water to your shower or sink without realizing why.
This issue is especially common in homes with:
- Low-flow showerheads or faucets
- Short water runs close to the unit
- Bathroom remodels using eco fixtures
We’ve seen tankless heaters fail to fire when someone simply wanted warm water to wash their hands or rinse a dish. That’s frustrating, and unacceptable in a high-end home upgrade.
Inconsistent Temperature, Long Waits
With a tankless water heater, the water must first reach a set flow rate, then be heated as it passes through a heat exchanger. This can cause:
- Delays of 30–60+ seconds before hot water arrives
- Fluctuating temperatures when multiple taps are running
- Intermittent cold bursts during showers
Hot-water waiting time depends on pipe length, flow, insulation and recirculation design. A pump can shorten the wait in either a compatible tank or tankless system, but it does not guarantee an exact delivery time or lower energy use.
Breakdowns and Replacement Parts: A Global Problem
Unlike standard tanks with universal parts, tankless systems often use brand-specific components manufactured overseas. When something breaks, you might be waiting weeks, sometimes months, for a replacement board or sensor to ship from abroad.
This is a key reason why experienced plumbers and general contractors often prefer tanks. They’re simple, fast to fix, and less likely to leave your home without hot water for days at a time.
Why Performance Matters in Remodels
If you’re upgrading your bathroom, kitchen, or installing a walk-in tub, you need water heating that works, on demand and under pressure. If your heater can’t keep up, that sleek new fixture becomes a cold disappointment.
Make sure your water heater matches your lifestyle and your home’s layout. What works in a 1-bedroom condo may fail in a 3-bathroom home.
Is Your Tankless System Struggling Already?
Have you noticed any of these signs?
- Inconsistent shower temperatures
- Cold surges when running two fixtures
- Hot water delays in distant bathrooms
- Service calls due to error codes
If so, it might be time to reassess whether your current system is the right fit.
Request a free evaluation and let our licensed remodeling pros assess your hot water setup before your next upgrade. We’ll help you avoid future frustration and wasted money.
04 / When Tankless Water Heaters Actually Make Sense
When Tankless Water Heaters Actually Make Sense
Despite all the downsides we’ve discussed, tankless water heaters aren’t always the wrong choice. In fact, under the right conditions, they can be an excellent solution for your hot water needs, especially when installed correctly and chosen based on proper capacity.
Smart Use Cases for Tankless Water Heaters
If you’re living in a small home, studio, or apartment without a basement, space savings alone may justify installing a tankless water heater. They can also be ideal in these scenarios:
- Homes with 10+ people who require continuous hot water use over several hours
- Properties with limited mechanical space or no basement for a traditional water heater
- Southwestern or southern homes where heaters are commonly mounted in garages
- Homeowners seeking a point-of-use heater for a guest bathroom or outdoor shower
Today’s high flow tankless water heaters can deliver up to 11 GPM (gallons per minute), making them more capable than older models that couldn’t handle multiple taps at once. Brands like Navien, Rinnai, and Noritz now offer smart systems that auto-adjust based on water demand, improving performance in real-time.
Walk-In Tubs: A Special Case for Tankless or Oversized Tanks
If you’re installing a walk-in tub, standard 40- or 50-gallon tanks may not cut it. These deep tubs often require 50–80 gallons of hot water to fill, depending on the model and size. That exceeds the capacity of most traditional water heater systems.
There are two smart options in this case:
- Install a larger 80-gallon traditional water heater with fast recovery
- Use a high-efficiency tankless water heater with a flow rate of at least 9–11 GPM
If space is limited or you want quick hot water refills between uses, tankless becomes the better fit, but only if it’s sized correctly and installed with attention to flow rate and local plumbing code.
See how our remodeling team integrates the right water heating solution into every bathroom design.
Best Tankless Water Heater Brands to Consider
Not all systems are created equal. Based on our experience with installations and client feedback, here are three of the best tankless water heaters currently available for residential use:
- Navien NPE-240A2 – Up to 11.2 GPM, Wi-Fi capable, dual stainless steel heat exchangers.
- Rinnai RU199iN – Recirculation capable with compatible accessories, compact size, ENERGY STAR certified.
- Noritz EZ Series – Retrofit-friendly, high-efficiency gas unit with advanced diagnostics.
These units perform well in high-demand homes when properly sized and installed by a qualified contractor. But remember, even the best tankless water heater won’t solve problems caused by poor planning or undersized plumbing.
Need help choosing? Our team matches water heater capacity to the exact demands of your home, whether you’re adding a soaking tub, upgrading to multiple bathrooms, or installing radiant heat.
Click here to get a custom system recommendation tailored to your next remodeling project.
06 / Rinnai Tankless Water Heaters
Rinnai Tankless Water Heaters: Recirculation Options and Performance Insights
Rinnai has earned a strong reputation in the U.S. for high-efficiency tankless water heaters, with popular models like the RU199iN and the upgraded RXP199iN. These systems are designed to deliver endless hot water with smart technology, but performance heavily depends on your plumbing layout and recirculation strategy.
Common Issue: Delayed Hot Water Without Return Line
Homeowners using the RU199iN often report long wait times, up to 3 minutes, for hot water in distant fixtures. This is common in large homes without a dedicated recirculation line. Fortunately, Rinnai offers several retrofit solutions:
- GTK15 Kit + Thermal Bypass Valve: Allows use of the cold water line as a return, bypassing the need for a dedicated loop.
- RSC199i / RXP199iN: Newer models with built-in pumps and smart scheduling features.
Keep in mind: Using the cold line as a return will cause the cold water line to run warm until purged.
Rinnai Models Compared
| Model | Built-In Pump | Recirculation Type | Fuel Type | Notable Feature |
|---|---|---|---|---|
| RU199iN | No | Optional (external with thermal valve) | Natural Gas / Propane | High-capacity, but retrofit needed for recirc |
| RSC199i | Yes | Thermal Bypass / Smart Scheduling | Natural Gas / Propane | Learning pump for peak usage |
| RXP199iN | Yes | Crossover Valve (no return line) | Universal Fuel | Confirm fuel compatibility and controls for the exact model |
Things to Watch For: Maintenance and Heat Exchanger Life
Water quality and maintenance requirements vary by model. Read the installation manual and warranty terms for the exact unit, and ask the installer whether local water requires treatment. Do not assume that a general water-softener recommendation addresses every water-quality issue.
Is Rinnai Right for You?
Rinnai remains a top-tier option, especially with newer models offering smart recirculation and WiFi control. But if you’re in an older home without a return loop, plan for added installation steps or consider whether a model with integrated pump is worth the extra upfront cost.
Get a free estimate to upgrade your system or explore recirculation installation options for your Rinnai heater.
07 / Noritz EZ Series
Noritz EZ Series: Warranty Power and Easy Retrofit Installation
If you’re upgrading from a traditional water heater and prefer minimal disruption, the Noritz EZ Series deserves a serious look. Models like the EZTR50 and EZ111 are purpose-built to simplify installation by aligning with existing tank-style plumbing and venting layouts. For homeowners who value convenience and longevity, Noritz provides an attractive balance of warranty coverage, reliability, and adaptability.
Top Features of Noritz EZ Models
- 25-Year Heat Exchanger Warranty: One of the longest warranties on the market, 10 years longer than Navien’s standard.
- EZ Retrofit Design: Inlet and outlet water lines match standard tank heater positions, reducing plumbing work.
- Compact Wall-Mount Profile: Designed to fit tight indoor utility closets or replace existing tank heaters without major rework.
Noritz EZTR50 vs Navien NPE-240S2
| Feature | Noritz EZTR50 | Navien NPE-240S2 |
|---|---|---|
| Heat Exchanger Warranty | 25 Years | 15 Years |
| Parts Warranty | 5 Years | 5 Years |
| Retrofit Friendly | Yes (EZ pipe match) | Requires replumb in most cases |
DIY or Pro Install?
Gas sizing, venting, condensate drainage and water connections must follow the specific manufacturer’s instructions and local permit requirements. Use qualified tradespeople and arrange the required inspections; a convenient retrofit layout does not make installation a simple DIY swap.
Who Should Consider Noritz?
Noritz is ideal for:
- Retrofitting homes with standard tank water heater layouts
- Homeowners who value extended warranty coverage
- Simple installs in closets, garages, or laundry areas
Get a free quote to compare Noritz vs Navien systems for your home layout and hot water demands.
08 / Choosing the Right Size Water Heater for Your
Choosing the Right Size Water Heater for Your Home
One of the most common mistakes homeowners make is installing a water heater, tankless or traditional, that doesn’t match the actual water demand of their home. Whether you’re remodeling or building new, selecting the correct size is essential to avoid cold showers, poor water pressure, or wasted energy.
Understand Your Flow Rate Needs
Tankless water heaters are rated by flow rate, measured in gallons per minute (GPM). To determine what size you need, add up the GPM of all fixtures that might be used simultaneously. For example:
- Shower: 2.0–2.5 GPM
- Bathroom faucet: 0.5–1.0 GPM
- Kitchen sink: 1.5–2.0 GPM
- Washer: 2.0 GPM
- Dishwasher: 1.5 GPM
If your family often showers while the laundry runs, a water heater that supports at least 6–8 GPM is a must. Larger homes with multiple bathrooms may require 9–11 GPM systems or dual-unit configurations.
Compare GPM and Temperature Rise
The higher your incoming water temperature, the easier it is for a tankless heater to deliver warm water. In colder climates like Washington State, the system needs to work harder to heat cold groundwater. This means you’ll need a stronger unit to achieve the same result.
As a general rule:
- Warm climates (incoming water ~70°F): Lower GPM units work fine
- Cool climates (incoming water ~40–50°F): Choose higher GPM with strong BTU output
Request a free evaluation and we’ll calculate the ideal water heater size based on your home layout, climate, and lifestyle.
09 / Final Verdict
Final Verdict: Choose the Right Water Heater for Your Home
When it comes to choosing between a tankless water heater and a traditional water heater, the right decision comes down to your home’s layout, your hot water habits, and your long-term goals.
If you value simplicity, low maintenance, and consistent performance, a high-efficiency tank with a recirculation pump might be your best choice. These systems are affordable to install, easy to repair, and deliver instant hot water, even to distant fixtures.
But if your home requires high-capacity output, space-saving solutions, or continuous hot water use, like in homes with walk-in tubs or radiant heating, then a properly sized high flow tankless water heater may serve you better.
Tankless Systems Are Evolving
New models like the Rinnai RU199iN, Navien NPE-240A2, and Noritz EZ Series are much more advanced than earlier generations. With improved sensors, better cold weather performance, and higher GPM ratings, these options now support whole-home usage when sized and installed correctly.
Still, these systems require a solid understanding of water heater capacity, local plumbing code, and proper electrical or gas upgrades. It’s not a DIY swap, it’s a carefully engineered installation.
Let Our Experts Help You Decide
At Bezruchuk Inc., we help homeowners across Seattle, Puyallup, and Bellevue avoid costly heating mistakes by matching the right system to the right home.
Whether you’re planning a bathroom remodel, converting your shower, or upgrading your water heating system to support a curbless shower or walk-in tub, we’ll guide you every step of the way.
Want to make the right investment? Let our licensed general contractors help you compare options, plan the layout, and ensure your new system meets code, flow, and warranty requirements.
Click here to request your free quote today or visit our Bathroom Remodel service page to see more projects and solutions.
Frequently Asked Questions
What is a tankless water heater and how does it work?
A tankless water heater heats water on demand as it passes through the unit. It doesn’t store hot water like traditional tanks. When you open a hot water tap, cold water flows through the heater’s coil system and is instantly heated before being delivered to your fixture.
How long do tankless water heaters last?
Most tankless water heaters last between 15 to 20 years with proper maintenance. However, annual flushing is required to prevent scale buildup, especially in areas with hard water.
Why does my tankless water heater take so long to deliver hot water?
Tankless systems need to reach a minimum flow rate before heating begins. Then, water must travel through your plumbing lines. Without a recirculation pump, this can cause delays of 30 to 60 seconds or more.
Are tankless water heaters more energy efficient than traditional ones?
Tankless water heaters are more energy efficient because they only heat water when needed. However, their higher upfront cost and ongoing maintenance may offset the energy savings over time.
Can a tankless water heater support multiple showers running at the same time?
That depends on the unit’s flow rate, measured in gallons per minute (GPM). Standard units may struggle to power two or more showers simultaneously. High flow models are better suited for larger households.
Do tankless water heaters require maintenance?
Yes. They must be flushed at least once a year to remove mineral buildup and maintain performance. Skipping maintenance may void the warranty and shorten the unit’s lifespan.
Is a tankless water heater a good option for a walk-in tub?
Walk-in tubs usually require 50 to 80 gallons of hot water. A properly sized tankless water heater can meet that demand, but it must deliver at least 9 to 11 GPM. In some cases, a larger traditional tank is more practical.
How much does it cost to install a tankless water heater?
The cost typically ranges from $4,000 to $7,000, including the unit and installation. Additional costs may apply if your home requires gas line upgrades, electrical changes, or venting.
Can I install a tankless water heater in a cold climate?
Yes, but make sure to choose a model rated for cold weather and have it professionally installed with proper freeze protection and insulation.
When is a traditional water heater a better option?
Traditional water heaters are better for homes with average hot water use, larger basements, and a desire for simpler, low-maintenance systems. They’re also more cost-effective for most remodeling projects.
Check manufacturer details for the Rinnai RU199iN, Navien NPE-240A2 and Noritz EZ warranty.
