Navien Tankless Water Heaters
Compare Every Model. Find the Right Fit for Your Long Island Home.
Why Navien?
Navien is the number one selling tankless water heater brand in North America, and for good reason. Their condensing technology delivers some of the highest efficiency ratings in the industry, and every unit is engineered for reliability, longevity, and ease of maintenance. At All Island Comfort, we specialize exclusively in Navien products because we believe they are the best tankless water heaters available for Long Island homeowners.
Navien offers four residential tankless water heater series, split into two categories: condensing and non-condensing. Condensing models extract more heat from exhaust gases to achieve higher efficiency, while non-condensing models offer a lower upfront cost with simpler installation requirements. Below you will find a detailed look at every model, including specifications, pricing, and our recommendations for different household sizes.
Side-by-Side Model Comparison
| Specification | NPE-A2 | NPE-S2 | NHW-AI | NHW-AE |
|---|---|---|---|---|
| Type | Condensing | Condensing | Non-Condensing | Non-Condensing |
| Placement | Indoor / Outdoor | Indoor / Outdoor | Indoor Only | Outdoor Only |
| Energy Factor | Up to 0.97 | Up to 0.96 | Up to 0.82 | Up to 0.82 |
| Max BTU Input | 199,900 | 199,900 | 199,900 | 199,900 |
| Max Flow Rate | 11.2 GPM | 11.2 GPM | 9.5 GPM | 9.5 GPM |
| Recirculation Pump | Built-in | Optional | No | No |
| Wi-Fi (NaviLink) | Yes | Yes | No | No |
| Venting Material | PVC (up to 60 ft) | PVC (up to 60 ft) | Stainless Steel | Not Required |
| Condensate Neutralizer | Required | Required | Not Needed | Not Needed |
| Dimensions (W x H x D) | 17.3" x 27.4" x 13.2" | 17.3" x 27.4" x 13.2" | 17.3" x 25.2" x 10.3" | 17.3" x 25.2" x 10.3" |
| Weight (199K BTU) | 77 lbs | 73 lbs | 62 lbs | 62 lbs |
| Heat Exchanger Warranty | 15 Years | 15 Years | 15 Years | 15 Years |
| Parts Warranty | 5 Years | 5 Years | 5 Years | 5 Years |
| Installed From | $7,900 | $7,800 | $4,540 | $4,040 |
Prices include complete professional installation with gas line connection, venting, and system testing. Actual cost may vary depending on gas line upgrades, venting complexity, and other site-specific factors. Financing available starting at 0% APR.
Condensing Models
Navien's condensing tankless water heaters are the most energy-efficient option available, achieving up to 0.97 energy factor by extracting additional heat from exhaust gases before they are vented. They use affordable PVC venting and require a condensate neutralizer for the acidic byproduct. These are our most recommended models for Long Island homeowners looking for maximum efficiency and long-term savings.
NPE-A2 Series
Premium Condensing Tankless Water Heater with Built-in Recirculation
The NPE-A2 is Navien's flagship residential tankless water heater and the model we install most often on Long Island. What sets it apart is the built-in recirculation pump and 0.5-gallon buffer tank, which means hot water arrives at your faucet almost instantly without the typical wait time associated with tankless systems. It achieves up to 0.97 energy factor, making it one of the most efficient water heaters you can buy.
The NPE-A2 also includes NaviLink Wi-Fi connectivity, allowing you to monitor and control your water heater from your phone. It supports PVC venting up to 60 feet, which makes installation flexible in most Long Island homes. Available in four sizes (150, 180, 210, and 240) to match any household demand.
Key Features
- Built-in recirculation pump and 0.5-gallon buffer tank for instant hot water
- Up to 0.97 energy factor for maximum efficiency
- Up to 199,900 BTU and 11.2 GPM flow rate (240 model)
- NaviLink Wi-Fi for remote monitoring and control
- PVC venting up to 60 feet (lower cost than stainless steel)
- ComfortFlow technology for consistent temperature delivery
- Available in Natural Gas and Liquid Propane
- 15-year heat exchanger, 5-year parts, 1-year labor warranty
Available Sizes
Best For
Homes with 2 to 4+ bathrooms that want the best efficiency, instant hot water, and smart home connectivity. Ideal for families that use multiple hot water fixtures simultaneously.
NPE-S2 Series
High-Efficiency Condensing Tankless Water Heater
The NPE-S2 delivers nearly identical performance to the NPE-A2 at a slightly lower price point. The main difference is that the recirculation pump is optional rather than built-in. If instant hot water is not a priority for your household, or if you plan to add recirculation later, the NPE-S2 offers outstanding efficiency and reliability at a better value.
Like the A2, the NPE-S2 features NaviLink Wi-Fi connectivity, PVC venting up to 60 feet, and ComfortFlow technology. It achieves up to 0.96 energy factor and is available in the same four sizes. It requires a condensate neutralizer like all condensing models.
Key Features
- Up to 0.96 energy factor for high efficiency
- Up to 199,900 BTU and 11.2 GPM flow rate (240 model)
- Optional external recirculation pump (add later if needed)
- NaviLink Wi-Fi for remote monitoring and control
- PVC venting up to 60 feet
- ComfortFlow technology for consistent temperature delivery
- Available in Natural Gas and Liquid Propane
- 15-year heat exchanger, 5-year parts, 1-year labor warranty
Available Sizes
Best For
Homeowners who want condensing efficiency without the premium for a built-in recirculation pump. Great for households that do not mind a short wait for hot water or plan to add recirculation later.
Non-Condensing Models
Navien's non-condensing tankless water heaters offer a more affordable entry point into tankless technology. While they are less energy efficient than condensing models, they do not require a condensate neutralizer and have a lower upfront cost. The NHW-AI is designed for indoor installation, while the NHW-AE is purpose-built for outdoor use with weatherproof housing and freeze protection.
NHW-AI Series
Indoor Non-Condensing Tankless Water Heater
The NHW-AI is Navien's indoor non-condensing tankless water heater, offering a significant step up from traditional tank water heaters at a more budget-friendly price than condensing models. It achieves up to 0.82 energy factor and delivers up to 9.5 GPM at a 35-degree temperature rise, which is plenty for most Long Island households.
Because it is non-condensing, the NHW-AI does not produce acidic condensate and does not need a neutralizer. However, it does require stainless steel venting, which costs more than the PVC used by condensing models. The front panel allows direct temperature adjustment and includes recirculation timer controls.
Key Features
- Up to 0.82 energy factor
- Up to 199,900 BTU and 9.5 GPM flow rate (199 model)
- Compact wall-mount design (17.3" x 25.2" x 10.3")
- Front panel temperature and recirculation controls
- No condensate neutralizer required
- Stainless steel venting required
- Available in Natural Gas and Liquid Propane
- 15-year heat exchanger, 5-year parts, 1-year labor warranty
Available Sizes
Best For
Budget-conscious homeowners upgrading from a tank water heater who want the benefits of tankless (endless hot water, space savings, longer lifespan) at a lower price point. Ideal for 1 to 3 bathroom homes.
NHW-AE Series
Outdoor Non-Condensing Tankless Water Heater
The NHW-AE is Navien's outdoor non-condensing tankless water heater, designed specifically for exterior installation. It features a weatherproof housing and built-in freeze protection, making it suitable for Long Island's climate. Because it installs outside, it eliminates the need for indoor venting entirely, freeing up interior space and simplifying installation.
The outdoor design means no venting materials to purchase or install, which helps offset the cost difference with indoor models. The control panel is located inside the unit for weather protection, and it includes a remote controller for indoor temperature adjustments. This is the lowest-priced Navien tankless option when you factor in the venting savings.
Key Features
- Up to 0.82 energy factor
- Up to 199,900 BTU and 9.5 GPM flow rate (199 model)
- Weatherproof outdoor housing rated for all seasons
- Built-in freeze protection for cold Long Island winters
- No indoor venting required (saves venting costs)
- Remote controller included for indoor temperature adjustment
- No condensate neutralizer required
- Available in Natural Gas and Liquid Propane
- 15-year heat exchanger, 5-year parts, 1-year labor warranty
Available Sizes
Best For
Homes with limited interior space, difficult interior venting paths, or homeowners who want the simplest and most affordable tankless installation. The outdoor placement eliminates venting costs and frees up utility closet space.
How to Choose the Right Model
Household Size
Count the number of bathrooms and hot water fixtures in your home. For 1 to 2 bathrooms, a 150K or 160K BTU unit is typically sufficient. For 3+ bathrooms or high-demand homes, go with 199K BTU or consider a multi-unit cascading setup.
Budget
Condensing models cost more upfront but save money over time through higher efficiency. Non-condensing models have lower purchase and installation costs but slightly higher monthly energy bills. Financing is available to spread out the investment.
Installation Location
Do you have space for indoor installation with proper venting? If not, the NHW-AE outdoor model eliminates venting entirely. Condensing models use cheaper PVC venting, while indoor non-condensing models need stainless steel.
Efficiency Priority
If minimizing energy costs is your top priority, condensing models are the clear winner with up to 0.97 energy factor versus 0.82 for non-condensing. The NPE-A2 adds instant hot water with its built-in recirculation pump.
Not sure which model is right for you? Our technicians will evaluate your home and recommend the best option during a free on-site assessment.
How Navien Tankless Water Heaters Work
Unlike traditional tank heaters that store and continuously heat 40-50 gallons of water, Navien tankless units heat water on demand as it flows through the system.
You Turn On the Faucet
When a hot water tap is opened anywhere in your home, cold water flows into the Navien unit through the cold water inlet.
The Gas Burner Fires
An eco-friendly, low-NOx stainless steel burner ignites automatically. The flame intensity adjusts based on how much hot water you need.
Dual Heat Exchangers Heat the Water
Water passes through Navien's durable dual stainless steel heat exchangers. Condensing models (NPE-A2, NPE-S2) recover extra heat from exhaust gases for up to 0.96 UEF efficiency.
Endless Hot Water Delivered
Hot water exits through the hot water outlet and flows to your faucet, shower, or appliance. The unit keeps firing as long as the tap is open, so you never run out.
On NPE-A2 models with built-in ComfortFlow recirculation, hot water is also kept warm in the supply lines so it arrives at the faucet almost instantly, with no waiting.
Industry-Leading Warranty Coverage
Navien was the first to offer dual stainless steel heat exchangers, and they back their products with one of the strongest warranties in the industry.
| Application | Type | Labor | Parts | Heat Exchanger |
|---|---|---|---|---|
| Residential | Standard / Controlled Recirculation | 1 Year | 5 Years | 15 Years |
| Uncontrolled Recirculation | 1 Year | 3 Years | 5 Years | |
| Commercial / Combi | Standard / Controlled Recirculation | 1 Year | 5 Years | 8 Years |
| Uncontrolled Recirculation | 1 Year | 3 Years | 3 Years |
Combi refers to combination potable water and space heating applications. For complete warranty details, refer to Navieninc.com. All Island Comfort handles warranty registration as part of every installation.
Navien Accessories & Add-Ons
Enhance your Navien tankless water heater with these optional accessories designed to improve comfort, protect your investment, and give you more control.
NaviLink Wi-Fi Control
Monitor and control your water heater remotely from your smartphone. Set recirculation schedules, adjust temperature, receive maintenance alerts, and track energy usage through the NaviLink app.
Compatible with: NPE-A2, NPE-S2HotButton On-Demand Recirculation
A wall-mounted button that activates recirculation when you want hot water. Press the button, wait a moment, and hot water is ready at the faucet. Built-in controller included. Ideal for homes without a dedicated return line.
Compatible with: NPE-A2, NPE-S2PeakFlow-S Scale Prevention
An environmentally friendly scale prevention system that protects your water heater from hard water mineral buildup. Extends the life of the heat exchanger and maintains peak efficiency without chemicals or salt.
Compatible with: All Navien modelsNaviCirc Recirculation Valve
An optional recirculation valve that makes installation easier when no dedicated return line exists. Installs at the farthest fixture and allows hot water recirculation without running new plumbing. External pump required for NPE-S2.
Compatible with: NPE-A2, NPE-S2Our Navien Services
Tankless Water Heater Installation
Professional installation for all Navien models. New construction, tank-to-tankless conversions, and replacements. Free on-site estimates.
Learn MoreTankless Water Heater Repair
24/7 emergency repair service. Error code diagnosis, heat exchanger descaling, parts replacement for all Navien models.
Learn MoreCondensate Neutralizer Service
Required for all condensing models. Installation, media replacement, pH testing, and drain line maintenance.
Learn MoreNavien Tankless Water Heater FAQs
What Navien tankless water heater models are available?
Navien offers four residential tankless water heater series in the US market. The condensing lineup includes the NPE-A2 Series (premium with built-in recirculation pump) and the NPE-S2 Series (high-efficiency without built-in pump). The non-condensing lineup includes the NHW-AI Series (indoor installation) and the NHW-AE Series (outdoor installation). Each series is available in multiple BTU sizes.
What is the difference between condensing and non-condensing?
Condensing models (NPE-A2, NPE-S2) extract additional heat from exhaust gases before venting, achieving energy factors up to 0.97. They use affordable PVC venting but require a condensate neutralizer. Non-condensing models (NHW-AI, NHW-AE) cost less upfront but use more expensive stainless steel venting and have a lower energy factor of up to 0.82. Over the life of the unit, condensing models typically cost less to operate.
Which Navien model is best for my home?
It depends on your priorities. If you want maximum efficiency and instant hot water, the NPE-A2 is our top recommendation. If you want similar efficiency at a slightly lower cost and do not need a built-in recirculation pump, choose the NPE-S2. For a budget-friendly option, the NHW-AI is excellent. If you have limited indoor space or difficult venting paths, the outdoor NHW-AE eliminates venting entirely. Our technicians can help you decide during a free on-site assessment.
How long does a Navien tankless water heater last?
With proper maintenance, Navien tankless water heaters are built to last 20 years or more. This is significantly longer than traditional tank water heaters, which typically last 8 to 12 years. Navien backs their units with a 15-year warranty on the heat exchanger, 5 years on parts, and 1 year on labor. Annual maintenance including heat exchanger flushing and filter cleaning helps maximize lifespan.
Do Navien tankless water heaters work with propane?
Yes. All four Navien residential tankless water heater series (NPE-A2, NPE-S2, NHW-AI, NHW-AE) are available in both Natural Gas (NG) and Liquid Propane (LP) configurations. LP models require different gas pressure settings (11" WC vs 3.5" WC for natural gas), which our technicians configure during installation.
Can I install multiple Navien units together?
Yes. For larger homes or commercial applications, Navien condensing units can be installed in a cascading configuration, linking two or more units together for seamless hot water delivery. This is common in homes with 4+ bathrooms, guest houses, or properties with high simultaneous hot water demand. We design and install multi-unit systems as part of our installation services.
What maintenance does a Navien tankless water heater need?
Navien recommends annual maintenance that includes flushing the heat exchanger with a vinegar solution to remove mineral buildup (approximately 45 minutes), cleaning the inlet water filter, inspecting the venting system, and checking the condensate neutralizer media for condensing models. Our repair team handles all maintenance services.
Is financing available for a Navien tankless water heater?
Yes. We offer flexible financing through Wisetack for all Navien installations. Plans range from 3 months to 10 years with APR starting at 0%. There is no hard credit pull to check your options, and you can apply in minutes. Loan amounts range from $500 to $25,000, making any Navien model accessible regardless of your budget.
Ready to Choose Your Navien?
Our certified technicians will help you select the perfect model for your home during a free, no-obligation site assessment. We serve all of Nassau and Suffolk County and are available 24/7. Check our coupons page for current specials.
Have questions? Check our FAQ page for more answers about Navien water heaters.