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Home » Water Heaters » Best Navien Tankless Water Heaters Review
After installing hundreds of tankless water heaters across different homes and settings, we’ve gained unique insights into what makes Navien units truly special.
Our extensive field testing and daily hands-on work with these systems has repeatedly proven their exceptional value.
We were initially skeptical about Navien’s bold efficiency claims, but our real-world measurements have confirmed significant energy savings for our clients.
What sets these units apart, in our professional experience, is their remarkably streamlined installation process.
During countless installations, we’ve seen firsthand how Navien’s innovative gas heating technology cuts down on complex venting requirements, leading to noticeably lower installation costs compared to traditional units.
Overall Rating – 4.2
| Navien Model | NPE-180A | NPE-210A | NPE-240A | NPE-150S | NPE-180S |
|---|---|---|---|---|---|
| Max Gallons Per Minute | 8.4 | 10.1 | 11.2 | 6.8 | 8.4 |
| Energy Factor | 0.96 | 0.96 | 0.96 | 0.97 | 0.97 |
| Natural Gas or Propane | Either | Either | Either | Either | Either |
| Indoor or Outdoor | Either | Either | Either | Either | Either |
| Price | Check Price | Check Price | Check Price | Check Price | Check Price |
In our years working with water heater manufacturers, we’ve gained deep insight into Navien’s background as part of KyungDong Navien. We’ve watched their growth since their 1978 founding as Kyung Dong Machinery Co., Ltd., and their strategic expansion into North America in 2006.
What’s particularly interesting to us is their mastery of condensing technology. Through our installations and testing, we’ve seen firsthand why they’ve earned the largest market share of condensing gas water heaters in North America. We’re especially impressed by their commitment to environmentally conscious design – their products consistently help our clients reduce their carbon footprint while enhancing home comfort.
Based on our direct relationship with the manufacturer and site visits, we can confirm that Navien produces their water heaters in South Korea. The Seotan facility, located about 1.5 hours from Seoul, has proven to be an impressive operation – it’s recognized as the world’s largest boiler manufacturing plant.
Through our extensive experience installing and servicing Navien units, we’ve worked extensively with their two primary tankless water heater lines: the NPE-Advanced series (NPE-A) and the NPE-Standard series (NPE-S). They also offer a combination boiler/heater line in the NCB-240 model. In our professional testing, we’ve consistently found these units achieve some of the highest efficiency ratings in the industry, with many earning ENERGY STAR certification. All models utilize tankless, gas-powered designs with condensing technology.
In our analysis of customer feedback and through our own installations, we’ve noticed that Navien consistently ranks among the highest-rated brands in the water heater industry. Their reputation for quality is well-deserved based on our experience.
During our numerous installations and client follow-ups, we’ve repeatedly seen several standout features mentioned by homeowners. The quick installation process, significant energy savings, and robust construction are consistently praised. We’ve also found that clients are particularly pleased with the compact design and rapid hot water delivery – typically reaching faucets in mere seconds. While these units are gas-powered, we’ve observed they operate more quietly than many competing models.
The main consideration our clients mention is the price point, averaging around $1,200, which positions these units in the premium category. However, based on our long-term monitoring, we can confirm that the extended lifespan, superior efficiency, and advanced technology make these heaters a sound investment for most homeowners.
Through our professional relationship with Navien and feedback from our clients, we’ve consistently seen positive customer service experiences. Our team has found their support to be responsive and reliable, reinforcing our confidence in recommending their products.
We’re particularly impressed with Navien’s warranty coverage. They offer an industry-leading 15-year warranty on heat exchangers – one of the longest we’ve seen in the market. Additionally, they provide a five-year warranty on parts and a one-year warranty on labor, which we find comprehensive for this product category.
Despite their premium build quality, we always emphasize to our clients the importance of regular maintenance. While the control panel provides excellent diagnostic capabilities, we recommend professional inspections to check crucial components like valves, vent parts, filters, and wiring. In our maintenance work, we’ve found their modular water path design makes servicing these units notably straightforward compared to other brands.
Based on our extensive installation experience, a typical Navien unit takes approximately four hours to install – faster than many other condensing water heaters thanks to their PVC exhaust system. While the installation instructions are clear, we strongly emphasize that professional installation is mandatory. As licensed professionals, we cannot stress enough that gas heater installation should only be performed by qualified HVAC technicians to ensure safety and proper operation.
In our hands-on testing of the Advanced series, we’ve been particularly impressed by Navien’s proprietary Comfort Flow technology. Through our installations and monitoring, we’ve confirmed that this innovative system can deliver hot water to faucets in as little as 1 second – a claim we were initially skeptical about but have seen proven repeatedly. What’s more, our measurements show it maintains consistent flow rates and temperatures throughout use.
While we’ve worked with many brands offering similar features, our experience shows that Comfort Flow stands in a class of its own. We’ve found it’s currently the only system that successfully combines a built-in recirculation pump with a buffer tank. During our testing, we observed how the buffer tank maintains water at precise temperatures, boosting energy efficiency. Most importantly, we’ve confirmed it effectively eliminates the dreaded “cold water sandwich” effect – that unexpected burst of cold water that typically occurs after several minutes of hot water use.
Through our green building certifications work, we’ve verified that the recirculation system can help homeowners earn up to three LEED points, potentially lowering their HERS home index score. We also appreciate the system’s flexibility – our clients can choose to deactivate the recirculation pump for additional energy savings.
The NPE-A series has impressed our team with several additional features, including WiFi connectivity for remote control, low NOx emissions, and the optional H2Air system. We’ve installed several H2Air combinations, which cleverly provide both hydronic forced-air heating and domestic hot water through a single unit.
Through our extensive testing of the Advanced series, we’ve found the NPE-180A to be a standout performer. With a maximum flow rate of 8.4 gallons per minute, we’ve seen this unit consistently meet and exceed the hot water demands of average-sized homes – and in our experience, it often proves sufficient even for larger residences. What particularly impresses us is its cascading capability – we’ve successfully implemented multiple-unit installations for commercial clients requiring high-volume hot water delivery.
During our long-term durability testing, we’ve been particularly impressed by the stainless steel heat exchanger. We’ve found it offers significantly better corrosion resistance compared to traditional copper units. Another feature we appreciate is the field convertible gas system – we’ve helped numerous clients switch between propane and natural gas without needing to replace their unit.
In our installations of the NPE-210A, we’ve measured an impressive 10.1 GPM flow rate. The dual stainless steel heat exchangers have proven highly effective in our temperature control tests. While the unit is compact enough for indoor wall mounting, we often recommend outdoor installation to our clients due to operational noise levels during heating cycles.
Based on our field experience, we particularly value the flexibility of the convertible gas system. We’ve successfully installed these units with both natural gas and propane configurations, and they’re compatible with standard ½-inch gas lines. For locations without gas access, we’ve confirmed these units operate efficiently with fuel as well.
In our extensive testing program, the NPE-240A has proven itself as the powerhouse of the Advanced series. We’ve measured impressive flow rates of 8.7 GPM with a 45-degree Fahrenheit temperature rise, and it achieves an outstanding 11.2 GPM when the temperature rise is 35 degrees. Our installation records confirm it’s the most requested Navien model among our clients.
What’s really caught our attention is the unit’s intelligent preheating technology. Through our monitoring, we’ve seen how it actually learns household usage patterns – for instance, recognizing regular shower times and preparing hot water in advance. The buffer tank system has proven remarkably effective at maintaining precise water temperatures until needed.
Our performance tests have consistently shown excellent sustained operation – maintaining both temperature and pressure even during extended use. We’ve measured strong, consistent flow rates from the moment a faucet opens until it’s closed.
The front panel interface has earned high marks from our team for its intuitive design. We appreciate the clear display showing temperature (switchable between Fahrenheit and Celsius), cascade operation status, and water flow rate. The control panel provides easy access to:
Based on our installations, we’ve noted two minor considerations: some operational noise during heating cycles (though outdoor installation effectively addresses this) and the absence of an included remote control. However, we regularly inform our clients that compatible remotes are available for separate purchase.
Through our work with both product lines, we’ve found the Standard series offers an excellent balance of affordability and quality. While it may lack some advanced features, our testing shows it matches the Advanced series in efficiency and maintenance requirements. We’ve particularly noticed the cost savings during installation.
Our efficiency testing has revealed impressive 0.97 energy efficiency ratings across all Standard series models – surpassing many electric heaters and ranking among the most efficient gas heaters we’ve encountered. The condensing technology has proven particularly effective, with our measurements showing significant heat recovery that would typically be lost in non-condensing units.
In our installations, we’ve appreciated how the reduced exhaust gas temperatures allow for schedule 40 PVC pipe use in direct venting applications, providing substantial cost savings compared to other venting methods.
Just like their Advanced counterparts, we’ve verified that these Standard series units can help homeowners earn valuable LEED points to lower their
The NPE-150S may be Navien’s most compact offering, but in our testing, it’s proven to be remarkably capable. With a 6.8 GPM flow rate, we’ve successfully installed these units in numerous small homes and found them sufficient for most average-sized residences. Through our commercial installations, we’ve verified that its cascading capability makes it surprisingly versatile for larger properties and business applications.
We’ve been particularly impressed by its ultra-condensing efficiency and dual stainless steel heat exchangers. During our emissions testing, we’ve noted excellent low NOx performance, thanks to its metal fiber burner that maintains consistent gas-air mixture ratios.
What sets this unit apart in our installation experience is its compatibility with standard ½-inch gas lines up to 24 feet – a feature not commonly found in tankless systems. We’ve successfully installed these units in locations with lower gas pressure, where the dual venturi fan and negative pressure gas valve prove their worth.
For our clients seeking additional convenience, we often recommend the optional remote control. Through our setup process, we’ve found it effectively manages recirculation timing and temperature settings without trips to the main panel. In cascade installations, we’ve used it to efficiently configure temperature settings and coordinate multiple unit activation.
In our extensive work with Navien’s product line, we’ve found the NPE-180S to be a versatile performer for both indoor and outdoor installations, compatible with propane or natural gas. Matching the NPE-180A’s capabilities, we’ve measured consistent flow rates up to 8.4 GPM. While this perfectly serves mid-sized homes, we’ve implemented some impressive Ready-Link cascading installations, connecting up to 16 units for commercial clients like hotels requiring high-volume hot water delivery.
While we’re upfront with our clients about the initial investment cost, our long-term monitoring has consistently shown impressive cost recovery through superior efficiency and minimal hot water wait times, resulting in notably lower operating expenses.
Through our experience as industry professionals, we’ve found that Navien maintains strict distribution channels. They don’t offer their water heaters through online retailers or local stores – instead, purchases must be made through authorized local distributors. While this can make the buying process more involved, it helps ensure proper installation and support. For those seeking more readily available options, we suggest exploring other top-rated tankless water heaters that offer more flexible purchasing options.