Navien Tankless Water Heater Reviews (Updated 2019)

Introduction of Navien Tankless Water Heater Reviews: It is not possible to think winter or even a day of summer without a water heater in this modern age. Before the invention of tankless technology, people used to boil their water in a bowl on fire which was laborious, time-consuming, poorly energy efficient and unsafe. To make that easy, Norwegian mechanical engineer Edwin Rudd came up with a solution by invented the automatic storage type water heater in 1889, after he settled to Pittsburgh, Pennsylvania (US). Keep up with the time researchers and technologists made many advancements to update the design and operational procedure of traditional storage type water heaters as well as modern tankless water heaters.

Today I would like to talk about the Navien Tankless Water Heater, a product of KD Navien. KyungDong Navien takes entrance in the world of modern water heater in 1978, about 100 years later on the invention of the automatic water heater by Rudd. In 1988 KD Navien emerged as the first company in Asia to develop and produce a highly efficient, environment-friendly boiler with condensing technology. This out of the box activity escalates the company as a leader in the condensing boiler market as well as creating space for the Navien tankless water heaters.

navien reviews

KD Navien design and marketed the industry best Tankless Water Heaters which are top quality, highly energy efficient, and emit decidedly less harmful chemicals like CO, CO2 or Nitrous Oxides. Thus it keeps a significant contribution to makes our world greener and healthier for a living. Nonetheless, Navien also introduces the most modern technological innovations in all of its products like exclusive ComfortFlow® technology, Dual Stainless Steel Heat Exchanger, Intelligent Preheating and many more to ensure continuous and instant hot water whenever you need. Stay with us, and we will tell you more such interesting stories about amazing Navien Tankless in our below reviews.

Top Six Navien Tankless Water Heaters on the Market


Weight (lbs.)

Flow Rate@35°F





11.2 GPM





11.1 GPM





11.2 GPM





10.1 GPM





8.4 GPM





8.4 GPM




Navien Tankless Water Heater Reviews

Navien NPE-240-A Review

People move from the traditional water heater to tankless due to get instant and continuous hot water flow. Now, the question is that tankless genuinely able to serve you instant hot water whenever you open your faucet. Might be not, as most of the tankless want few moments to heat up and remove stagnant cold water from pipes between heater and fixtures (known as a sandwich effect). However, don’t need to be upset, Navien NPE-240-A Tankless Gas Water Heater comes with a solution that ready to supply you instant and continuous hot water to maximize your comfort.

Navien NPE-240-A Tankless Gas Water Heater

The 2013 AHR Innovation Award Winner Navien NPE-240-A is the best tankless water heater from this manufacturer as it offers a lot of amazing features and easier to use than others. Among the points, one is recirculation of water inside the loop between your faucet and heater which keeps H2O warm during delivery by minimizing the sandwich effect. It happens due to built-in recirculating pump and insulated buffer tank technology of Navien on demand water heater.  

This model is easy to install as it designed to work with 2 inch PVC/CPVC pipes - 60-feet long Navien venting and fit with ½ inch natural gas lines that are common for most of the homes of America. However, you need to employ professional plumber for installation work to get long life and 5 to 15 years warranty on different parts.

An LCD with convenient buttons and optional remote control system allows you to set a suitable temperature and even set a timer based on your hot water requirement. It also helps you to save water bill significantly.

So, what else you are waiting for, click here to check the latest price and purchase one for your home or commercial space.


  • ½ gas pipe capable up to 24'
  • Field convertible gas system
  • Ultra condensing efficiency
  • Dual stainless steel heat exchangers
  • Low NOx emissions (≤20ppm)
  • SCH 40, 2" venting up to 60'
  • Front panel command center
  • Ready Link Cascading features


  • Built-in buffer tank assists in maintaining the continuous and massive flow rate of hot H2O
  • The recirculating pump helps to supply hot water promptly without waste
  • Intelligent preheating technology helps to keep water warm before your use
  • Stainless steel dual heat exchanger prevents rusting and ensure speed flow


  • Substantially more weight, weighing 92 pounds than other models.
  • Somewhat expensive that you may have to push your capability to the border
  • Quite large for a small family whose lives in condos or one washroom apartment


Q: Can I run this unit with propane gas? 

A: Yes, this unit comes set-up for Natural Gas, but the field convertible gas system permits you to use LP gas too with the included LP Gas conversion kit.

Q: In case of install outside, does it need any cover top of the unit? Does it come up with cover or lid?

A: Yes, you need to cover it up and required special outdoor vent kit to install. Navien does not supply any top or lid and vent kit. You have to collect those additionally. 

Q: Is it possible to set 180°F in this model?

A: Navien NPE-240-A come up with the factory setting of 120°F, and it allows maximum 182°F temperature. So, for commercial use, you can set the temperature up to 182°F.

Q: What type of power source required to run this unit?

A: 120V AC, 60 Hz, and minimum 2 A current required to run this unit.

Q: What is the highest and smallest flow rate?

A: At 35°F (19°C) the maximum flow rate is 11.2 GPM, and the minimum is 0 GPM.


The simple furnish, dual stainless steel heat exchanger, ultra-condensing efficiency, high-class ComfortFlow technology, and field gas convertibility features churned out this Navien NPE-240-A Tankless Gas Water Heater one of the best choices in the tankless arena. Though it is a little expensive and cumbersome to maneuver, once you start using, it will not seems to weigh your pocket.

Navien NPE240S-NG Premium Reviews

Are you concern about the efficiency of your existing water heater? Navien NPE240S-NG Premium Condensing Tankless Gas Water Heater Natural Gas has the highest energy efficiency among the tankless water heaters, and that is 0.99 EF according to the Energy Star Directory. Not only this, but Navien NPE-240s also achieved the 2015 AHR innovation award. Advanced condensing technology helps Navien Standard series to ride on this pride. It will also help you to achieve LEED point and reduce HERS score. Navien tankless means generate more heat using the same power and save energy bills. So, stay with the winner.

Navien NPE240S-NG Premium Condensing Tankless Gas Water Heater Natural Gas

​If you compare Navien NPE-240S with Navien NPE-240A, you will find both are identical except recirculating pump and buffer tank system. However, NPE-240S-series is more cost savings than the 240A due to its higher energy factor to the ultra-modern condensing system.

NPE-240S model is also lighter than the NPE-240A machine, which makes easy to wall hanging and quicker installation. It also occupied less space of your home. It also offers 15 years warranty for dual stainless steel heat exchanger like other Navien water heaters.


  • Field convertible gas system
  • Ultra condensing efficiency
  • Dual stainless steel heat exchangers
  • Low NOx emissions (<20ppm) and compiled with SCAQMD 1146.2
  • ½ gas pipe capable up to 24'
  • Vent up to 60’ with 2" venting pipe (Approved materials: PVC Schedule 40)
  • Cascading capable 16 units in a single group
  • Front panel control system


  • Ultra condensing technology will give significant energy savings with high efficiency
  • Dual stainless steel heat exchanger more resistant to corrosion and less mineral scaling and deposits
  • Dual venturi fan and negative pressure gas valve allows you to run the device even in lower gas pressure
  • Less water pressure drop due to its simple modular water path
  • Compact wall hanging design facilitate multiple units in a single confined area


  • Required frequent maintenance
  • You have to wait a few moments to get hot water at your faucet due to the cold water sandwich effect
  • This device run only NG or LP, so if you have no connection of gas line at your home, it will not work for you.


Q1: Does the Navien NPE-240S consist of the remote control in its package?

A1: No, it’s an optional accessory. You have to order it additionally. You will get details about in NaviLink.  

Q2: If I brought this product from, can I get warranty support from Navien?

A2: According to the policy, the warranty will be void if you bought any products from the internet, other e-commerce sites, or any wholesalers or retailers whose have no authorization. It also voids if you will not employ approved installer/plumber for installation. So, if you buy from Amazon, you will not get any warranty support. However, if you install your device by any approved installer, then the plumber can claim warranty on behalf of you to the Navien Inc.

Q3: Does NPE240-S includes installer kit in its package or need to purchase separately?

A3: Navien includes a kit for installation which consists of a bracket to hang it on the wall and the connecting fittings. However, you have to purchase a copper pipe, gas pipe or PVC for venting additionally.

Q4: Is the Navien NPE-240s louder? 

A4: No, it is a quieter device and makes almost no noise during running.


The Navien NPE240S-NG Premium Condensing Tankless Gas Water Heater Natural Gas is an excellent device for the American homeowners and commercial users. It guaranteed to deliver a performance that you and your family will be satisfied. Those who love eco-friendly devices this low NOx and energy efficient Navien tankless gas water heater is the perfect choice for them. The internal parts design with durable materials like stainless steel heat exchanger as well as aesthetics exterior looks makes it is a great device.

Navien NPE-240A Premium Condensing Tankless Gas Water Heater

Are you ready to experiencing the best hot water to maximize your comfort, Navien NPE-240-A Premium Condensing Tankless Gas Water Heater brings the next-generation condensing technology with the simple installation process and advanced features for you. Navien design this device such a way that eliminates almost all the complications of the old tankless heaters and makes it a perfect solution for the new age.

Navien NPE-240A Premium Condensing Tankless Gas Water Heater

​Navien NPE-240-A is the most advanced condensing tankless water heater in the industry which has exclusive ComfortFlow technology with built-in recirculating pump and buffer tank ensure instant hot water flow. By using this, you can earn up to 3 LEED point along with the reduction of HERS score for your home. It achieved 2013 AHR innovation awards too.

Navien 240A premium has an optional HotButton, and WiFi enabled NaviLink system which allows you to save your energy bill by removing cold water sandwich effect as well as wireless control through your mobile phone.


  • Ultra condensing efficiency
  • Two stainless steel heat exchangers
  • Utilizes existing ½ inch gas line up to 24’, No need to install a new line
  • Field convertible gas system from NG to LP
  • Intelligent preheating technology
  • Low NOx emissions (≤ 20ppm)
  • SCH 40, 2" venting up to 60'
  • Cascading capable of linking up to 16 units in one group and up to several groups
  • The safety features include ignition operation detector, flame rod sensor, power surge fuse, water temperature high limit switch, exhaust temperature limit sensor and so on.


  • Smart preheating technology will give you instantaneous hot water supply
  • Navien NPE240-A premium emit decidedly less harmful gases like CO, CO2, NO
  • It also helps to reduce about 960lbs. of Carbon Monoxides emission yearly thanks of its ultra-condensing technology
  • The intelligent front panel control system helps to set the various features as well as identified error quickly and efficiently
  • NPE240-A premium is designed for long lasting and durability use year after year without any hassle


  • It is a bit costlier than tanks water heater in the market
  • Improper venting may hamper the performance of the water heater
  • Fittings can develop leaks over time


Q1: What included in the package?

A1: The box contained the following items –

  • A quick Installation Manual
  • Wall Mounting Bracket
  • Four Tapping Screws & Anchors
  • LP or NG Conversion Kit
  • Two 2" Vent Termination Caps
  • Four 2" Wall Flanges
  • Spare Parts (fuse, etc.) and
  • An Installation & Operation Manual

Q2: Besides the accessories and parts come up with the package what else I have to purchase for installation?

A2: To install the device you need to purchase some more additional items like a water pipe, vent pipe, gas pipe based on your home requirement. Before purchase, those take expert plumber advice for reducing the wastage and the cost of operation.

You also have to buy isolate valve kit which helps you to shut the delivery line without stopping the whole house water line, Condensate neutralizer cartridge, anti-scaling filter, and etcetera.

Q3: What is the temperature range of this device? What is the suitable temperature for household use?

A3: You can set 98°F to 140°F in this device. However, the factory setting is 120°F, and you can rise it up to 182°F. However, for household set beyond 140°F is dangerous and void your warranty.

Q4: What is the hot water flow rate of this device?

A4: At 35°F temperature the flow rate is measured 11.2 GPM, and 7.8 GPM found in 45°F

Q5: What is the energy efficiency factor?

A5: According to Energy Star Directory the energy factor is 0.97 (97%) in the USA and 0.99 (99%) in Canada.


The lustrous design and extremely durable Navien tankless water heater will eradicate all of your worries regarding maintenance along with providing uninterrupted service for a long time. Once you install it appropriately and in a safe environment, the Navien NPE-240-A Premium Condensing Tankless Gas Water Heater work for you without creating any hassle. Navien accommodates all advanced features and premium materials to build this unit and offer 15 years warranty for its customers. Finding such combinations is rear. You can depend on and set it for your lovely home or commercial space.

Navien NPE-210A Review

You invested in Navien tankless water heaters means you planted a tree and took a step forward to the greener world. Why I’m saying this because Navien always tries to incorporate all advanced technologies into its products. Moreover, the unique industrial science it applies to its NPE A and S series tankless water heater is condensation. The principal task of the condensing technology is to use the airway/vent heat. The vent heat helps to raise the temperature of the cold water during entering to the heat exchangers. Thus it saves energy uses and protect the environment.

Navien NPE-210A Premium Condensing Tankless Gas Water Heater

The Navien NPE-210-A Premium Condensing Tankless Gas Water Heater is no an exception of that. You will find all the latest technology like ComfortFlow, remote control or HotButton, preheat and many more including ultra-condensing tools.

We will try to discuss all of its features and favorable and unfavorable conditions in below reviews a bit more elaborately.


  • Two heat stainless steel heat exchanger: primary and secondary
  • Field convertible gas system
  • Ultra condensing efficiency
  • PVC, CPVC or Polypropylene venting, 2’’ for 60-feet and 3’’ for 150-feet
  • Well-matched with existing 1/2’’, ¾’’ or 1’’ gas lines
  • Easy conversion between field gases NG to LP
  • Cascade system for commercial uses


  • Recirculating pump and 0.4 gallons buffer tank provides you steady hot water flow
  • Intelligent preheating technology gives you instant hot water without waste your time and water
  • Suitable for wall hang both in indoor and outdoor
  • Consist of a flow detector to monitor and adjust hot water flow
  • Comes with a built-in leak detector which saves you from the possible damage to the heater
  • Consist of a digital screen on the front panel of the water heater
  • Energy certified and energy factor 0.97 (97%)


  • The flow detector frequently clogs and shut down the whole system
  • Warranty will be void if purchase from the internet or any e-commerce sites and not installed by an approved plumber
  • Warranty covers only one repair per parts


Q1: What is the flow rate of the Navien NPE-210A?

A1: The flow rate DHW is 10.1 GPM@35°F

Q2: How much water pressure required to run this heater?

A3: the required water pressure is 15 to 150 psi.

Q3: How much gas pressure required to ignite the burner?

A3: The operable pressure for Natural Gas is 3.5’’ to 10.5’’ WC (Water Column) and for Liquid Propane 8’’ to 13’’ WC.

Q4: Which types of safety devices included in this device?

A4: The Flame Rod, Ignition Operation Detector, Water Temperature High Limit Switch, Exhaust Temperature High Limit, APS, Sensor, Power Surge Fuse and many more safety devices included with this device.

Q5: What accessories come with this product?

A5: An Installation & Operation Manual, Quick Installation Manual, Wall Mounting Bracket, Tapping Screws & Anchors, two Vent Termination Caps, two Wall Flanges, Natural Gas to Propane Conversion Kits come with this product.


We try to describe both the pros and cons of the Navien NPE-210-A Premium Condensing Tankless Gas Water Heater in our Navien reviews. We see that the disadvantages are not outrageous than the advantages. Moreover, the carbon steel body and stainless steel exchangers increase its life up to 20 or more years and comfort technology makes it is a cost-effective option. Hope you feel the features are excited and buy one to meet up your home or commercial hot water requirement.

Navien NPE-180A Review

Is space stands between you and your water heater as the main hindrance during installation? Are you love Navien hot water heater but looking for a more compact model? Then you come to a right place. The Navien NPE-180-A Premium Condensing Tankless Gas Water Heater is a bit compact than other water heater devices of Navien. So, you can install it in your small home space without thinking much. It is also lighter than others Navien models.

However, compact and lightweight not means that you will not get others technological advancement from this product like another Navien’s. Navien tries to manufacture all of its products with the highest care. You will find ComfortFlow, Smart Preheating, Condensing, Digital Control, and many other features in this Navien water heater too. 

Navien NPE-180A Premium Condensing Tankless Gas Water Heater

Please stay with me to see more features and benefits of this fantastic tankless water heater.


  • Maximum Input: 150,000 BTU/H
  • Suitable for both Indoor and Outdoor Installation
  • Residential or Commercial
  • ½” gas pipe capable up to 24’
  • Field convertible gas system
  • Ultra condensing efficiency
  • Dual stainless steel heat exchangers
  • Low NOx emissions (≤ 20ppm)
  • SCH 40, 2” venting up to 60’
  • Cascading capable
  • 2” PVC, CPVC, Polypropylene Venting up to 60’
  • Less Water Press Drop
  • Clever Preheating Technology


  • Compact space saving design that you can install on any wall
  • No fluctuation in temperature during hot water supply due to the dual heat exchanger
  • No scaling, no deposition and rusting due to stainless steel heat exchanger
  • No tension either you bought NG or LP Navien water heater due to its field convertible option
  • Factory built-in temperature control switch helps you to monitor, adjust and detect defect easily
  • Highly sensitive control feature helps to maintain higher temperature flow as per demand in case of multi-unit cascading


  • Though Navien claims to be instantaneous hot water, this is somewhat misleading. It takes 40-45 seconds to deliver hot water at your faucet.
  • A chance of experiencing leakage from the inside parts of the water heater after a few months of use.
  • A bit costlier than other tankless water heaters in the market


Q1: What is the flow rate?

A1: the hot water flow rate of Navien NPE-180A premium is 8.7 GPM @ 35°F.

Q2: What is the maximum input capacity?

A2: the maximum input capacity of this units is 150000 BTU/H, whoever the minimum output capacity is 15000 BTU/H.

Q3: What is the suitable voltage to run this unit?

A3: The suitable voltage to run this model is 120 volts Single Phase and 60 Hz.

Q4: What is the dimension and weight of the Navien NPE-180A?

A4: NPE-180A is 27.4 inches tall, 17.3 inches wide and 11.4 inch deep in size with 75.5 pounds weight.


Besides save your precious space, the Navien NPE-180-A Premium Condensing Tankless Gas Water Heater also helps to cut your energy bills. The ultra-condensing technology aid to limit the emission of harmful chemicals like NOx, CO or CO2 which turns it into an eco-friendly device. The sturdy design and stainless steel heat exchanger makes it a long lasting water heater too. Offering 8.5 GPM flow rate (DHW) doesn’t mean that it is the most robust water heater in the market, but it is better than many other weakest too. However, as a trusted company Navien always try to offer the best option for its customers. So, I believe, once you start using this fantastic machine, you will fall in love.

Navien NPE-180S

If this is the case of judging the performance of any water heater, in that case, the output is all about. As an experienced company, Navien does not manufacture so many models of the water heater, but all are so efficient that they outperform than any non-condensing competitors. The Navien NPE-180-S-NG Premium Condensing Tankless Gas Water Heater Natural Gas can run with a lower input of 150K BTU/H instead of 199K BTU/H of non-condensing water heaters. 99% energy efficiency is the highest in the tankless industry which you only found in Navien NPE-180S models.

Navien NPE180S-NG Premium Condensing Tankless Gas Water Heater Natural Gas

Navien NPE-180S means more output for the money, lower installation costs and lower operating costs for its customers which makes it is a smart choice to all.

The Navien review is not the end here; we will try to discuss more on this fantastic product below. However, if you desire you can check the up-to-date price and offers from Amazon.


  • Ultra condensing efficiency, Natural Gas
  • Two stainless steel heat exchangers
  • Utilizes existing 1/2" gas line
  • Field convertible option
  • Intelligent preheating technology
  • Dual Venturi
  • Sensor for air pressure and heat exchanger water flow
  • Built-in valve for water adjustment and negative pressure gas
  • Smart Display controller


  • Compact design and lightweight takes up less space when mounted on a wall
  • Intelligent preheats technology to assist in delivering water in a higher temperature
  • Digital LCD screen shows the temperature and other settings in a bright color
  • Adjustable temperature range 98-140 degrees Fahrenheit
  • Lower installation and operating costs for the homeowners
  • 2015 AHR innovation award winner
  • You can earn more LEED points and lower HERS scores for your home
  • Energy Star certified
  • 15-years warranty for heat exchanger


  • Installation of the gas-powered unit requires venting
  • Can get expensive, especially with add-ons


Q: Is Navien NPE-180S suitable for 185 sq. meter house?

A: Yes! It is sufficient to supply hot water at your 185m2 (2000 ft2) home with two bathrooms. It can generate 4.2 GPM DHW flow @ 67°F which is enough for large showerhead (2 GPM) or cloth washer (2 GPM) in winter. 

Q: Is there any difference between NPE-180 A and NPE-180 S model?

A: Yes! The main difference between this two model is a recirculating pump and buffer tank. NPE-180A have a built-in recirculating pump with buffer thank, and 180 S has no such thing. However, to operate this recirc. Pump A models need extra power. Therefore, S models are 2% more energy efficient than A models.

Q: Is it perfect to install outdoor?

A: Yes! You can install Navien NPE-180S at outdoor. In that case, you have to buy an outdoor vent kit from Navien.


The Navien NPE-180-S-NG Premium Condensing Tankless Gas Water Heater is perfectly all right for a large or medium home with 3-4 bathrooms. It can generate 8.4 GPM hot water flow with maximum 150K BTU input. The interior components are constructed by premium quality materials to ensure durability and longevity. Having a Navien heating system means lower your energy bill and a much smaller carbon footprint. It offers an exclusive 15-years manufacturer’s warranty, but to avail that you must have to employ a professional HVAC technician for installation.

How to Choose the Right One?

As a prominent and reputable company, Navien has a range of products with distinct features. They mainly produce condensing type gas tankless water heaters which are the best energy efficient device than any other non-condensing tankless heaters in the market. Because of what, they are the top listed company in the Energy Star ratings. Navien manufactured water heaters both for household and commercial applications. Now the question is that which one is suitable for you or meets your purpose perfectly? If you go through the following steps, hope it will help you to find your answer.

1. What is the Temperature Range?

Temperature is an essential factor for any water heater. Low or high-temperature water is not acceptable to anyone. Icy water in a winter day where outside temperature might be minus 30 will give a numb feeling, on the other hand overly hot water will scalding your skin.

So what will be the suitable temperature settings for a tankless heater? We know that Navien Tankless Gas Water Heater usually comes with a factory setting temperature of 120 degrees Fahrenheit (49°C), whereas the maximum temperature range is 185 degrees Fahrenheit (85°C). 120°F is the perfect temperature for you – maybe or maybe not? According to WHO, water temperature equal or more than 120°F will cause scalding within 5 minutes time which is dangerous for children, disable or elderly persons. Further, if you set a lower temperature than 120, it may feel cold. So, in times of shower or bath, you can set 120°F but mix cold and hot water by open both the cold and hot water faucets.

In case of washing clothes or dishes, you may set temperature 140°F or higher to get a good result. However, in tankless water heater amount of gas consumption will not directly depend on temperature settings as it will not burn gas when water is not in demand. On the other way, I can say that the amount of gas consumption is very insignificant relate to increase or decrease water temperature.

However, each Navien water heater comes with an LCD and temperature control interface with up and down button so that the customer can set preferable temperature effortlessly. You will also find an optional HotButtonTM system in Navien NPE Advance series which will allow you to push the button to activate the internal recirculation pump and gas-fired burner to heat water whenever you need and save energy.  

2. Navien DIP Switch Settings:

As I said, Navien on demand water heater comes with a preset temperature of 120°F. This temperature electronically controlled by PCB (Printed Circuit Board) of the water heater device. In Navien, there is two different way to control the output water temperature: by dip switches of main PCB boards and remote controller.  

In addition to the main circuit board (PCB), you can find the dip switches on the front panel too. Moreover, each location contains two sets of dip switches to control the functionality of the water heater. The circuit board dip switches are preset from the factory and not changeable manually. The two sets of dip switch on the front panel are responsible for configuring the water heater’s pump & recirculation, display, well pump, storage tank & solar system, lime alarm, high altitude, Cascade Venting, and Gas Type settings.

Dip switches

Figure above shown the settings of Dip switches.

Dip switches also allow you to set intelligent preheating function. Smart preheating system memories the pattern of hot water uses and start preheating before the awaited draw. If you are a working person and maintain a schedule of shower or bath, then you can set the timer on the remote controller according to your need of warm water by this function.

3. Navien Temperature Setting:

To set the desired water temperature on your Navien hot water heater, you can follow the steps stated below, or you also survey the instruction manual.

By default Navien tankless comes up with a factory setting of 120°F. To change this setting first check that all the hot water faucets closed, and ensure that the internal circulator and or any external circulating pumps are off. In case of any hot water outlet remains open then you can set the temperature from 98-110°F (37-43°C).

Then you have to press the Up [+] or Down [-] buttons until reached the desired temperature on the LCD. When the display starts flashing, you can able adjust the temperature. After complete your adjustment the screen will stop flashing means the temperature setting stored. Once set the temperature will remain unchanged in case of a power cut down too.

You will find the relationship between temperature range and the water temperature in the below table:

Temperature Range

Adjustment of the Water Temperature

98°F - 120°F (36°C – 50°C)

1°F or 0.5°C increments

120°F-140°F (Fahrenheit mode) 50°C-60°C (Celsius mode)

Press the + or - buttons for 2 seconds to adjust in 5°F or 2°C increments

Keep in mind that without installation of any recirculation line (internal or external) the tankless water heater Navien will not provide any hot water instantly at your fixtures.

In our earlier part, we said that the maximum range of temperature setting is 182°F. So, you may think that how you can reach that temperature range. Don’t worry, we explain it here. There is two mode of temperature control in the front panel: Low and High. By pressing Up [+] and Down [-] button simultaneously for 10 seconds, you can swing from Low to the High mode and vice versa. However, must remember that the High mode is for commercial use only. The range of industrial temperature start from 140°F (60°C) and up to 182°F (83°C), and it is essential to maintain this range during commercial use to get warranty support.  

4. Navien Tankless Water Heater with Recirculating Pump:

The best Navien tankless water heater introduces a unique ComfortFlow® system in its NPE-A models first ever in the tankless history, and till now you will not find this in other brands. It consists of a built-in insulated buffer tank and a recirculating pump which provides the following benefits –

  • Elimination of any minimum flow rate requirement
  • Elimination of any hot/cold/hot stacking—the ‘cold water sandwich’ effect
  • Eliminate waiting time to get hot water delivery to fixtures, which results in less water wasted

Though folks choose tankless type water heater to get instant hot water, most of the models in the market do not do it. You have to wait few moments as after opening the tap, tankless heater ‘ON’ and gas burner start heating the water in condenser then hot water travel through the pipe to the faucet, but prior that the stagnant cold water between the lines of the heater and the fixture need to flash out. We called this condition as ‘cold water sandwich.’ Usually, it happens in traditional tankless water heater when it turns on and makes hot water then turns off, cools for a moment or so, then again turns on. Suppose, you open the valve to wash your hand and stop, then another member of your family turns the hot water back on the right after you did, and they will experience a shock of cold water in between cycles. With thanks to the circulation pump and buffer tank, this will not happen in case of NPE-A models of the Navien tankless water heaters.

It is normal that when your water heater is in off condition, pipes between you and your NPE-A heater become cold, the water inside the pipes cools down too. The built-in recirculating pump of NPE-A will work to keep the water warm by moves the water around through the tubes. So you have not wait for hot water at your faucet. However, it consumes energy. Though, you can improve this situation by using another superb technology called HotButtonTM.

Now we need to know how HotButton solves this problem. After you push the HotButton, the internal recirculation pump of NPE-A device and gas-fired burner activate to heat the water in the supply lines. Once, that cold water is gone, the heater stops heating. You no need to run the water until it gets hot. This internal circulation process saves you water and money. Navien heating system ensures instant and continuous hot water flow whenever you required will leads you to reduce wastage of water. Thus it will help you to save up to 30% of your water bill.

5. What is the Flow Rate of Navien?

Water flow rate is the primary concern for most of the non-condensing tankless heater in the market. The flow rate is the measurement of hot water flow per minute. Most of all express it by gallon per minute (GPM) or Litter per minute (LPM). You no need to worry about flow rate if you have a storage heater, or you are a single user. However, for multiple users or diversified uses like taking a shower by two or more person at a time and or simultaneous use of a washing machine and taking a shower will require a sufficient flow rate. Usually, for multiple applications 10 to 11 GPM flow rate will be better to meet up hot water requirement satisfactorily.

Navien on-demand water heater is designed such a way that it brings about all the hot water needed by you, and for as long as you need it. 

Here we describe a table for DHW flow rate vs. temperature rise of different models for your understanding.








35°F (19°C) temp. rise

6.8 GPM (25.8 L/M)

8.4 GPM (32 L/M)

10.1 GPM (38 L/M)

11.2 GPM (42 L/M)

45°F (25°C) temp. rise

5.3 GPM (20 L/M)

6.5 GPM (25 L/M)

7.8 GPM (30 L/M)

8.7 GPM (33 L/M)

67°F (36°C) temp. rise

3.2 GPM (12 L/M)

4.3 GPM (16 L/M)

4.2 GPM (16 L/M)

5.0 GPM (19 L/M)

5.2 GPM (20 L/M)

5.6 GPM (21 L/M)

5.7 GPM (22 L/M)

For more details, you can check the Navien Engineering Documents or Service manual.

6. How Much Electricity or Power Does A Navien Unit Consume?

Navien tankless gas water heater is a high energy efficient device as per energy star certificate. The energy factor is 0.97 UEF / 0.99 EF which is the highest in the industry and much more than any traditional tank system.

However, the maximum power consumption is 200 W (max 2 A), and 350 W (max 4 A) if an external pump connected. To operate it you will need a power supply of 120V AC, 60 Hz.

You will get more details on electricity or power consumption in the service manual or engineering documents of Navien. Furthermore, it is essential to know the exact voltage requirement to check whether it matches with your existing outlets or you need to upgrade your circuit breaker before purchase.

7. Navien Tankless Water Heater Warranty:

No doubt as a tankless water heater Navien is the best in the market, but for a new customer, the warranty will bring a confidant. Keep this in mind Navien put the highest emphasis on warranty issue and offer a comprehensive policy on it. Please go through the table below –




Heat Exchanger


Standard or Controlled Recirculation

1 year

5 years

15 years

Uncontrolled recirculation

1 year

3 years

5 years

Commercial or Combi

Standard or Controlled Recirculation for units produced on or after Jan’2016

1 year

5 years

8 years

Standard or Controlled Recirculation for units produced on or before Jan’2016

1 year

3 years

10 years

Uncontrolled recirculation

1 year

3 years

3 years

Knowing about the warranty will also tell you how much coverage you get from the manufacturer. You also need to understand that the warranty only covers parts replacement for one time and if required any repairs in the future must come out of your pocket. For more details on full warranty policy, you can visit

8. What Power Source Do You Need?

Before deciding to purchase any water heater, it is essential to check the existing home wiring system. As any miss match identified after made purchase, you have to incur financial losses both for return the product (for shipping charge) and or change the wiring system.

Indeed to operate the best tankless water heater Navien you need to use 120 VAC, 60 Hz, minimum 2 A current. Using tolerantly high or low AC voltage may cause hamper on the operation and may reduce the lifespan of the device.

Significant Focuses About Navien

Navien Tankless water heater specs

We like to share some significant specs of Navien Advance and Standard series products below –


“A” (Advanced) Series

“S” (Standard) Series

Heat Capacity (BTU/H) NG/LP


15k to 19k

15k to 19k


150K to 199K

150K to 199K

Efficiency Ratings




EF for Canada (NG/LP)



Flow Rate

35°F (19°C) temp. rise

11.2 GPM (240A)

11.2 GPM (240S)

45°F (25°C) temp. rise

8.7 GPM

8.7 GPM

67°F (36°C) temp. rise

5.6 GPM

5.7 GPM

Water Pressure

15 – 150 psi


Electronic Ignition

Vent Type

Force Draft Direct

Installation Type


Natural Gas Supply Pressure (from source)

3.5 in WC - 10.5 in WC

Propane Gas Supply Pressure (from source

8 in WC - 13 in WC

Minimum Flow Rate

0.5 GPM, <0.01 GPM for A models

Connection Size

Cold Water Inlet

¾ in NPT

Hot Water Inlet

¾ in NPT

Gas Inlet

¾ in NPT

Power Supply

Main Supply

120volt AC, 60 Hz

Max. Power Consumption

200W (max 2A), 350W (max 4A) with external pump connected



Cold Rolled Carbon Steel

Heat Exchangers

Primary/Secondary Heat Exchanger: Stainless Steel

Vent System

Exhaust Vent

For Canada: 2" or 3" PVC, CPVC, Polypropylene
For the U.S.: 2" or 3" Special Gas Vent Type BH (Class II, A/B/C)

Intake Vent

For Canada: 2" or 3" PVC, CPVC, Polypropylene
For the U.S.: 2" or 3" Special Gas Vent Type BH (Class II, A/B/C)

Vent Clearance

0’’ combustible

Safety Tools

Flame Rod, Ignition Operation Detector, Water Temperature High Limit Switch, Exhaust Temperature High Limit Sensor, Power Surge Fuse, APS, and so on.

VIDEO: NPE-210S Tankless Comparison

Navien NCB Combi-Boiler Video

Where to buy Navien Tankless water heaters

Navien assures world-class quality in everywhere it sold its product. Currently, it’s holding the highest market share for condensing gas water heaters in North America as well as ranked top in technology patents. Navien global headquarter is in South Korea and export its green technology products to over 30 countries with leadership, efficiency and customer service.

From its North American headquarters situated in Irvine, California, KD Navien operates three training centers at California, New Jersey, and Ontario; and selling its products throughout Canada, Mexico, and the United States. Navien products are sold through and installed by professional contractors to assure superior performance and exceptional durability.

You can also buy it from Amazon, but in that case, you have to contact Navien authorized installer to install and for any future warranty claim purposes.

Navien tankless water heater installation

Navien water heaters are compact in design and suitable to install both indoor and outdoor. So, you will not think much about it. However, if you want warranty support, you have to follow the Navien installation rules. You must have to employ a licensed plumber, a licensed gas fitter, and or a professional service technician.

Secondly, you have to choose a place for installation where you can maintain a minimum clearance as per recommendation on the instruction manual in case of an indoor setting. For outdoor use, you have to avoid the moist or humid place to get better performance.

Generally, the installation process follows the below mention steps –

Step 1: Before Installing

Select appropriate location

  1. Keep proper clearance: For Indoor – minimum 9 inch at the top, ½ inch at Back, 4 inches at the front, 12 inch at the bottom and 3 inches at each side; For outdoor – a ½ inch at the back.
  2. The installation must maintain the manufactured home construction and safety standard, Title-24 CFR, Part # 3280 and CAN/CSA Z240 MH Series for mobile homes. Also, follow all local code and or the contemporary National Fuel and Gas Code (ANSI Z223.1/NFPA 54) in the USA, or the Natural Gas and Propane Installation Code in Canada (CAN/CGA B149.1).

Step 2: Installing

  • Unpacking the box: After unboxing check whether the following items come appropriately or not. 
  1. Navien Water Heater
  2. Operational Manual and Instruction Manual
  3. Wall mounting bracket
  4. Tapping screw and anchors
  5. Vent terminators
  6. Wall flanges
  7. Conversion kit
  8. Spare parts
  • Check and read the rating plate carefully before connecting the gas line for the gas type and pressure
  • Mounting on the wall and remove the front cover by unscrewing
  • Connect gas piping in a fresh line
  • Connect water piping (there are two types of connection procedure, one for internal circulation and another or external circulation settings)
  • Condensate drain connection, connected to the ½ inch condensate outlet fitting at the bottom of the device and water must spill into the exhaust connection to fill-up the condensate trap.
  • Check Venting System for indoor vertical vent termination or horizontal vent termination or side wall or roof installations.
  • Electrical connections of the control panel, power, etc.

Step 3: After Installation

  • Opening all the valve
  • Operating the water heater
  • Measuring the inlet gas pressure
  • Installing front cover
  • Check for the maximum water flow
  • Final Check

You will get more details on each point in Quick Installation Guide of Navien at

Navien vs. Rinnai

Navien and Rinnai both are very renowned and experienced company. KD Navien started its journey in 1988, in Korea. Whereas, Rinnai established in 1920 with the hand of Hidejiro Naito and Kanekichi Hayashi in Japan. However, Rinnai sold its first tankless water heater in 1999.

Rinnai has a broad range of products than Navien, but Navien covers all customer need with its small scale. All the products of Navien are made with ultra-condensing technology, whereas some models of Rinnai use this system. Though both the company produced efficient products which are the best-selling product in the market, Navien is a bit more energy efficient than Rinnai.

To give a clear idea on both brands, we share here a table of differentiation between Navien NPE-240A and Rinnai RUC98iN model as both are using condensing technology.

From the table mentioned above hope, you can understand the difference between the two brands quickly. The performance and quality almost the same but the Navien water heater are more energy efficient and environmentally friendly than Rinnai.

Navien Tankless water heater problems

Navien manufacturing all of its product with the utmost care. However, it may occur any issues due to improper installation or user interference. Usually, in the moment of arising any problems, different sensors detects it and show error code in front panel display.

Here we mentioned some such kind of common problems: Ignition failure, Temperature sensor error, Heat exchanger overheated, exhaust gas temperature error, flame loss, and noise occurs after ignition, the abnormal memory of PCB, etc.

Navien flow sensor problems

The function of the Navien flow sensor is to detect water flow in GPM for steady hot water supply. However, it may stop working due to damage or water leakage problems and unable to identify flow any more. Effect of that, ignition system will not start on time. An expert plumber may diagnose it by visual inspection and replace the sensor or repair the leak for reset.

Navien Tankless water heater prices

Navien maintains a healthy balance between performance and cost. Although, it always set a competitive price for its customer against offering the best quality products. You can check the price on amazon for all of its product. The cost of the product may vary with other online sites or e-commerce platforms around $100 based on offerings like shipping cost or spare parts. Keep it in mind that the price of ‘A’ series will be a little higher than the ‘S’ series because of the recirculating pump and buffer tank. 

Navien Tankless water heater maintenance

Maintenance is a must for every gadget. Proper and scheduled maintenance can increase the lifespan of any device. Navien is no an exception of that; it also required scheduled maintenance. Though the Navien water heaters made of solid carbon steel body and stainless steel heat exchanger, corrosion or oxidization is less of an issue than with usual tanks, some parts will wear out over time.

Cleaning and draining the water heater, flashing the heat exchanger, cleaning inlet water filter, recirculating filter or air intake filter are the part of regular jobs of maintenance. On the other sides, valves, venting parts, and filters are all worsened over time. Electrical and Electronic parts, such as the control panel, may also need maintenance once every few years to repair or replace any loose or damaged components. Whatever the problem arise, always take professional advice and do regular maintenance for longevity. 

Final Thought:

Over many years, Navien established itself as a technology leader in the arena of condensing tankless water heater industry. Utilizing many years of experience, it tries to incorporate innovations into its products to make those more efficient, energy savings and user-friendly. This continuous innovation trigger to achieve skyrocket growth.

After grabbing a significant share in Asian markets, Navien decided to expand its business towards Western Countries like European Countries, America, Canada, and Mexico. Since then, KD Navien becoming one of the fastest growing companies in the home comfort sector in North America. Navien also set up their training center and dealer network in America to spread out the condensing technology all over the U.S.

Nowadays, Navien is well known for its state-of-the-art technology, high efficiency, and reliable quality. Sophisticated engineering and robust design abetted Navien to achieved international recognition in condensing tankless water heaters, combi-boilers, and boilers technology. Moreover, they are firmly committed towards their customers to high-quality products with best after sales service facilities.

Finally, we try our best to uphold all the technological advancement besides drawbacks in our Reviews of Navien Tankless Water Heater. What I love most is produce the product with low emission, which leads us to build a greener world. With Navien on demand water heater, it will be guaranteed to get value for all the money spent.

  • Updated a couple of months ago
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