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 11-15 of 28 reviews

"Very unsatisfied, unit defective, warranty not honored"

1.0 rating
Very Unsatisfied

This is a poorly designed unit for Alaska, within months of installation, the three way valve quit and a new one installed, then the pump stopped working and Navien refused to honor their warranty on parts. Representative said the unit was not installed properly, the service person took a picture of the installation and texted it to the representative and asked how it was installed improperly and the rep would not reply. We have invoices of over $1000,00 in repairs this unit has cost us. The pressure sensor unit quite and cost $431.00 additional and we then had the unit replaced with another brand. If there is a class action suit pending, I want to part of it.

Lane E. Olson

Wasilla, AK


1.0 rating
Very Unsatisfied

3.5 years ago did an oil to gas conversion. The contracting firm said to go with Navien as they are very efficient. Perhaps when they are able to actually run. It's been a nightmare so far. Internal valve failures, error codes, etc. And now, during the coldest weather in many years we have been without heat for 3 days. Still waiting for a 3-way valve to arrive so the technician can rip out a bunch of parts in front of where it's located to replace (way in the back of unit). How can this part not be readily available in the ny Metro area? And the fact that, even though the $45 part is covered under warranty, I will be paying the hourly installation for this as well. I am seriously considering junking this piece of garbage and buying a more reliable (and better designed/maintainable) unit. Stay the heck away from this thing!!!!!!

S. Ray

Longs Island, NY

"Unbelieveable so far. I've already contacted a lawyer. I see a lawsuit coming against Navien, the installer or both."

1.0 rating
Very Unsatisfied

Nothing has worked correctly. There's been human error upon installation. A part was not working in the system. Navien will be out of business this continues.

Michael veves

Haverhill, MA

"Company policy stinks"

1.0 rating
Very Unsatisfied

I am writing out of frustration. I had to replace my unit because of a bad heat exchanger. My house was built in 2013 so the unit was only 4 years old. Navien replaced the boiler but since my labor warranty was only for one year I had to pay $1000 to the plumber to put the new one in. I called to register the new boiler and was told that this one will pick up the warranties where the old one left off. So I asked if this one craps out on me say in a few months I will have to pay for the labor again and the response was yes I will have to pay for the labor. Who has heard of such bad company policy. I wonder if there is a class action suit against this company.

Elizabeth Sakarellos

Greenport, NY


1.0 rating
Very Unsatisfied

Repeated failures involving no-heat or hot water. Three-way valve replaced twice in two years. Leaks anti freeze and water from overflow valves (pt?).

Bob Ruscitto

Barnstable, MA

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