Navien NCB Boilers

Navien NCB Boiler Overview

The Navien NCB is a condensing gas combination boiler with an efficiency rating of 95.0% AFUE. It was named an Energy Star Most Efficient 2015 product and is available in three models — NCB-180, NCB-210, and NCB-240. It is designed to save space and occupies up to 80% less space than a traditional floor standing boiler with tank water heater. The NCB features dual corrosion-resistant stainless steel heat exchangers with a separate stainless steel flat plate heat exchanger for domestic hot water. The system can use 2″ PVC for venting up to 60 feet and can easily be converted from natural gas to propane operation. For situations with very high domestic hot water demands, the NCB can be cascaded with Navien’s NPE tankless water heaters.

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Consumer Reviews of Navien NCB


  • Very Satisfied
  • Somewhat Satisfied
  • Neutral
  • Somewhat Unsatisfied
  • Very Unsatisfied
  • #2 of 4 Navien Boiler
  • 32% of customers recommended

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Navien NCB Boiler Reviews

Showing 21-25 of 25 reviews


1.0 rating
Very Unsatisfied

If you buy a Navien tankless water boiler do yourself a favor and go to Walmart and buy a couple of electric heaters as well because you're going to need them when your unit continuously fails. I had a NCB 180 installed three years ago. Every winter it has failed in some way or another leaving my family without heat for days. First it was flame loss then my two way valve quit working now my igniter switch is junk. The idea of saving money because it's high efficiency goes right out the window when you use the money you save to pay your plumber for all the repairs he needs to make. Do your research before you buy and save yourself the headache.


Erie, PA

"Poor quality, horrible warranty."

1.0 rating
Very Unsatisfied

The 5 year warranty covers parts, not labor. So when the plumber needs 3 hours to replace 10 cent o-rings rest assured those o-rings are fully covered. You'll still be on the hook for his time. Makes me happy I invested in this junk.

Eric. A

Wantagh, NY

"Big problems"

1.0 rating
Very Unsatisfied

I'm in the midst of trying to fix this problem. Installed June, 2016, hot water sporatic, sometimes none for most of the day…after two calls to the installer, **** ******* of Eagle Energy in Raynham, stopped answering my phone calls, did not respond to messages nor to emails. I called the manufacturer, they gave me phone numbers of 4 contractors who had training in installing this system. I have one now who said the installation was done all wrong and there is no inspection sticker on it, so apparently the unit was not inspected. He said because it was not installed correctly it is not under warranty. He says he can redo it from the ground up…for at least $2500, maybe more. I've already spent $500 on it, and the original cost was $8600. I'm wondering if it's worth fixing, after reading these reviews…is it throwing good money after bad. And I've been told that **** ******* is now out of business. I wonder what my recourse is. I've written to Better Business, the Attorney General and to 'solveit7', so I'm hoping someone can help. My husband and I are 78 and 79, we don't know how to deal with this, beyond what we've done.

Donna Coats

Brockton, MA

"My personal boiler review"

5.0 rating
Very Satisfied

I have owned my Navien boiler for almost two years now. I have been living in the same house with 3 of my friends for these two years, and it has been working with no problems since then. I like how quiet and efficient it is and honestly I have no complaints about it. I would definitely recommend this boiler to anybody looking for a new one because it is the greatest one I have ever owned.

San Diego, CA

"Efficient heat compared to forced air"

5.0 rating
Very Satisfied

I had my boiler installed last fall (September 2014) and I love it. We converted to a hydronic air handler from a traditional natural gas forced air furnace. I feel it delivers a much more even heat and is a lot more efficient. I also like the fact that we have essentially unlimited hot water now as well. I have recommended this unit to several of my friends. If I buy another property, I would definately invest in the same setup. Lastly, I really appreciate the small form factor it has, it freed up some room in my garage.

Anchorage, AK

Other NCB Reviews

Online reviews of the NCB appear to be mixed. On, a post from a homeowner trying to choose between the NCB and a similar Lochinvar unit found most replies favoring the Lochinvar, although one member stated that he liked his NCB and had no problems with it. In another post on the site a member mentions that Navien has updated their boiler line three times in five years, and for that reason he cannot support the product.

NCB Warranty

The warranty for the Navien NCB boiler is comprised of the following:

  • 10-year heat exchanger warranty
  • 5-year parts and other components warranty
  • 1-year labor warranty

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