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 16-20 of 28 reviews

"Do not buy a Navien"

1.0 rating
Very Unsatisfied

I used a Navien trained licensed plumber to install 2 Navien ch-240n asme high efficiency hot water boiler combo in November 2011. Since the installation I have spent more than $1000 dollars in repairs, with one boiler failing once and the second one failing 4 times. We were left with no heat or hot water. Their trained plumbers who came out to address the issues failed to follow Navien protocols, resulting in me not being reimbursed for parts under used that were under warranty. Navien's position is the plumbers are independent contractors, and they are not responsible for their behavior or action. As a customer of Navien be prepared to be on your own if you have a problem with their product. I have not found Navien to be accommodating or sympathetic to my needs or concerns, do not buy this product!!!!! The follow ups are nightmares.


Boston, MA

"Robbing Peter to pay Paul"

2.0 rating
Somewhat Unsatisfied

I've spend over 1000 dollars in the past 3 years since the new installation Apparently, though not yet determined, there was an incorrect install. Now I need to find yet another 'expert' technician- if one exists in my area. I'm sure there is, but wish I installed the 'tried and true' plain vanilla gas low efficiency boiler at this pot. It's a horse race of Navien vs bmw (my 535xi) who will succeed in extracting the most $ from my pocket.



"Not at all good and Navien knows it"

1.0 rating
Very Unsatisfied

Would like to start a class action suit. Navien is requiring a $1600-ish retrofit and line-flush to fix a design issue they have. This is the 3rd time without hot water in a two week period, even as the service company did first a unit and screen flush, (lasted for 10 days and then again, no hot water) and then a 4-hour, whole-house flush and screen/unit clean. Lasted 3 days. And we are on a water softener systems so don't tell me it is hard water of some sort. Our prior boiler lasted 18 years; this is less than 18 months. The newer Naviens have the $900 valve they want me to buy, as part of the design of the new units. This is not a model improvement, it is a fix of a known design flaw. (I'm a design engineer; I know the difference)

J Nelson

Williamson, NY

"Very unreliable"

1.0 rating
Very Unsatisfied

There have been multiple problems with the system and it is only a few years old. The first one that was installed was finally replaced a short time after being installed. The new one also has had multiple problems. In January I had to pay $1100 for a repair. This morning, May 17, I had no hot water. I can't go through this any longer. I never know when another problem is going to arise. Before I had this heating system installed I had a very old oil system that never gave me a problem. I converted to gas and got a nightmare with this system. Very unreliable.

K. Cardilli

Stamford, CT

"No problems"

5.0 rating
Very Satisfied

I have install about 20 of the Navien combo unit 240 model. I had one call back and that was because the lady son accidentally turned the emergency switch off. I am planning to install one in my house. Two days ago I went to look at one that was install by another contractor and the contractor installed a feed regulator valve which in not necessary because it caused the system to go into error. There is no need to install a feed regulator valve because it has a built in one. The pressure on the system keep going low and the system was shutting down. I took it out and hot water and heat was sailing.

Big Joe 3479988669

Brooklyn, NY

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