Navien Combi CH-240 Boilers

Navien Combi CH-240 Boiler Overview

The Navien Combi CH-240 is an on-demand combined ("combi") unit which heats water for central heating as well as for hot showers. This tankless boiler can be set up either inside or outside the house.

Features and specifications of the Navien Combi CH-240

  • It has two non-corrosive stainless steel heat exchangers. The heat exchangers have an energy efficiency of 91% when using natural gases and 92% when using propane.
  • It comes with a remote control that includes water temperature control, 24 hour scheduling and a user-friendly LCD display.
  • This boiler comes with an external sensor. Any changes in external temperature will lead to an automatic response from the boiler to either initiate central heating or halt it.
  • It has a built-in water leak detector and carbon monoxide monitoring system.

Safety precautions when using the Navien Combi CH-240

  • Ensure the boiler is adequately vented.
  • Ensure the water temperature is regulated, especially when children and the elderly are in the house. Do not set the water temperature above 125° F.

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Consumer Reviews of Navien Combi CH-240


  • Very Satisfied
  • Somewhat Satisfied
  • Neutral
  • Somewhat Unsatisfied
  • Very Unsatisfied
  • #3 of 4 Navien Boiler
  • 10.34% of customers recommended

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Navien Combi CH-240 Boiler Reviews

Showing 1-5 of 28 reviews


1.0 rating
Very Unsatisfied

Put in a new heat pump in the fall of 2014. I've had nothing but problems with the system. It seems to always go down on the coldest days of the year. I had to have a venter assembly put in this week March 2019 and my warranty is now up. I'm thinking it may be time to scrap this system and go with something else that's reliable!

G. Contractor


"Nightmare! Absolute Nightmare!"

1.0 rating
Very Unsatisfied

The radiant side never worked from the beginning despite the installer, who I picked from the Navien website, being on the phone with them. Lived with wood heat and the hot water side until after a year and a half, the whole system broke. I had a new installer I again got from their website come out to service it. Imagine my surprise when he told me the whole thing was installed incorrectly. After two weeks, he got Navien to ship a new Exchanger. Two days later the Module went out. After having shipped that a week later, we again had hot water. If you're counting, that's three weeks without hot water in the middle of winter. Two weeks later, the whole unit burns up. Now, Navien refuses to warrant it further due to faulty installation. They said they were not responsible for the work of installers that they listed on their website. I now only have hot water because I was able to reconnect an old electric water heater I found. Absolute Nightmare! Do NOT buy under any circumstances. Their service is crap. You're always waiting at least a week for a part. And then they don't stand behind their work or the work of people they recommend.

Eric Winkler

Yamhil, OR

"Hate It! I'm cold."

1.0 rating
Very Unsatisfied

It was installed after Sandy. We have had to call the plumber every winter at least once. Woke to no heat again today. The parts are under warranty, but not the price of the plumber to install the part. What I save in gas I spend in plumbers and electric heaters.

Jane P

New York

"Totally unreliable-DONT BUY"

1.0 rating
Very Unsatisfied

I echo the other negative reviews. Do not buy. Mine has broken down in each of the last 3 winters. No heat or hot water. While they cover the parts, not the labor. I have spent approximately 1500 in repairs.


Merrick, NY

"Navien boilers are crap"

1.0 rating
Very Unsatisfied

Ch240 installed 01/01/2012. Last year (1018 ) it has always been trouble but last year I spent $1,000.00 having Gandy Installations come by to keep it running. At year-end, it was leaking half a gallon in 24 hours, through the burner. I paid Gandy's bill of $156.45 today to come by and confirm it was leaking. Today I also paid Gandy $866.25 to install a new burner. Navien supplied the boiler but I paid the cost to get it running and all the parts they sent were not installed and would add another 2 1/2 hours or $400.00 making the total $1422.70 to fix. They say they will put them in next when it quits…Bad engineering, Can't them make an insert or just send a new boiler. Can't believe it would take longer than the 8 hours in total to replace this. And the cost is outrageous and reliability pee poor. Never again…

Thomas King

Surrey B.C.

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