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.

Questions about this model?

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 21-25 of 28 reviews

"Waiting for repairs"

1.0 rating
Very Unsatisfied

I may change my evaluation in a week, but for now I am disappointed and very unsatisfied with the Navien ncb 240 combo boiler. I am waiting for a water leak repair and my chosen heating company is being held up for a go-ahead because Navien in New Jersey insists on a water sample before authorizing parts. The original installer sub-contracted as he is a builder and I want to work directly with a heating and fuel company. I had a nyserda (nys) grant to help with the installation and was given glowing reviews of this heat and hot water system. It began to leak in November 2016 and was repaired under labor and parts warranty. Now the same leak has occurred and I will have to pay for labor. Ok, now a week has gone by, the system still drips water on to all of the internal parts and the company is hedging on the repair because they want to say that my well water is the problem. If this is the case I should have been fully informed before installation that I needed my water tested first. Also, I have a whole-house water filter installed and a water softener. I would say, buyer beware. You will hear more excuses why the system shuts down than you can imagine. Before you buy, it's all roses and what a great company. If my repairs will amount to as much as a new product, I will donate the Navien back to the company and buy something else. I see the Bosch has great reviews. If Navien comes though soon, I may change my tune, but today I am discouraged and feel taken for a ride.

J Hyland

Nassau, NY

"Awful Noise"

1.0 rating
Very Unsatisfied

The unit started making an awful noise and the company that installed it keeps sending people here but none of them have any idea what the problem is. Just sent and email to Navien. We'll see if they fix the problem.

J. Pagan

West Roxbury, MA

"Terrible experience"

1.0 rating
Very Unsatisfied

Installed ch-240 in rental unit May 2013. Failures began March 2014 and got worse over time. Tech support kept telling my technician to replace one part after another. Water pressure sensor was replaced at least 4 times under warranty. In the New England winter of 2016 the unit was failing about once a week. Navien's technicians would only have my guy replace parts 1 at a time. I had to replace the unit in December for the safety of my tenants (including a baby). Made calls to Navien. They refused to compensate me since their technician did not say to replace the unit. They did not seem to care if their customers suffered.

Barry J

Cape Cod, MA

"First one recalled, on second unit still having problems"

1.0 rating
Very Unsatisfied

We installed a Combi heating/water unit made by Navien. Middle of winter and unit breaks down. No heat, no hot water and total freeze up in water lines. After trying to repair, Navien sends out a new updated, revised model. This winter again with no heat, no hot water. 2 visits from plumber. There should be some kind of class action lawsuit against this company as I am sure we are not the only ones experiencing this. This has turned into an expensive venture. Considering ripping out second unit and replacing with standard heating system. Do not buy!!!!!!

Rhonda Pouladian

Boston, MA

"Never Again"

1.0 rating
Very Unsatisfied

Our contractor had a Navien boiler installed at the end of 2010. Since that time, I have spent over $2000 in parts and labor to keep the unit running. While the Navien warranty has expired, the company will not consider supplying parts at reduced cost in an effort to maintain customer satisfaction. Under no circumstances at all would I ever consider purchasing a boiler from Navien.

Bruce Belden

North Kingstown, RI

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