Navien, Inc. introduces a new 120,000 BTU/h model to the NPN non-condensing tankless water heater lineup. The NPN-120E is the fourth model introduction to the NPN-E (exterior) series, and just like the other three models in the series (NPN-160E, NPN-180E and NPN-199E), the new size is offered in separate natural gas and liquid propane configurations Read more