NPE-240S2
Features of the NPE-240S2
The NPE-240S2 is the largest and most powerful high efficiency condensing tankless water heater from Navien. The S2 at the the end of this model number represents that it is the (S) Standard version and the (2) is the second generation, which is the newest and most recent version from Navien released in 2021.
The S which stands for Standard doesn’t have all the bells and whistles that the A or Advanced models offer in a tankless water heater. Maybe you don’t need the extra features and see them as just additional parts that can break down over time. Or maybe you simply just want a high efficiency water heater and that’s all.
Whats the difference between the Standard and the Advanced Navien tankless?
The Advanced system gets you a built in buffer tank and a built in re-circulation pump. That allows you to use your tankless for hot water as well as some heating options throughout your home, things like a towel warmer, hydronic floors, or forced air could be good examples. If you are looking for a system that just heats water extremely efficiently, then the NPE-240S2 is the tankless for you!

NPE Tankless Sizes
The tankless unit we are discussing here is the NPE-240S2 from Navien, this is the most powerful system in this series. The 240 number in the model name represent how much heat the unit can produce to heat water up. For the NPE-240S2 you can expect a MAXIMUM output of 199,000 BTU/H. The amount of heat generated is directly related to amount of hot water a tankless can produce.
The temperature of the incoming water that a tankless needs to heat can significantly affect how much hot water is produced. For example, a Canadian home in winter can see their homes incoming water temperature dip to 5 degrees Celsius, which is pretty cold. A tankless needs to heat that 5 degree water up quite a lot to make that morning shower comfortable! Therefor, the more power (BTU/H) your tankless model can produce the more hot water you get in your home. This is how Navien differentiates their tankless models, by power rating (BTU/H).
We highly recommend the Navien NPE240 S2 in most homes throughout Ontario and Canada. The power and hot water generation are suitable for homes with 2-3 bathrooms and an average sized family. If you have more bathrooms, higher occupancy, or a basement apartment then this is definitely the model that you should be considering. If you do find that there is not enough hot water these systems are very easily twinned together to double the hot water production available for your home.
Navien NPE-S2 Models
NPE-240S2 Specifications
- Natural gas – 13,000 – 199,000 BTU/H
- Propane – 13,000 – 199,000 BTU/H
- 95% efficiency
- 67°F temp rise – 5.8 GPM (22.1 l/m)
- ½ gas pipe capable up to 24′
- Field convertible gas system
- Ultra condensing efficiency
- Dual stainless steel heat exchangers
- Low NOx emissions (20ppm)
- SCH 40, 2″ venting up to 75′
Interested In Buying a NPE-240S2 Navien Tankless
We sell, install, and service Navien tankless water heaters and truly believe in the tankless system. If you have any question or concerns give us a call or message us as we will love to chat ANYTHING tankless.
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647-925-1930
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