NAVIEN vs. RINNAI Water Heaters

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NAVIAN vs. RINNAI On-Demand Water HeatersTankless water heaters, also known as on-demand water heaters, provide hot water whenever you need it. They are more efficient than most storage tank water heaters and take up less room than their storage tank counterparts.

But, tankless on-demand water heaters can be more expensive initially than storage tank water heaters. They are almost always mounted to the wall, requiring professional installation. Tankless water heaters only run on natural gas or propane. So, if your water heater runs on electricity, you’ll have to convert or stick with a storage tank water heater for now.

Two of the best on-demand tankless water heaters brands are Navien and Rinnai. If you’re in the market for a new water heater, which should you choose? Here are the details on Navien vs. Rinnai on-demand water heaters. And don’t hesitate to reach out to our Severna Park water heater experts if you have any questions!

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Uniform Energy Factor (UEF)

The Uniform Energy Factor (UEF) is the metric that shows how efficient residential and commercial water heaters are. The higher the UEF, the more efficient the tankless water heater is.

Both Navien and Rinnai have condensing and non-condensing tankless water heater models. Condensing on-demand water heaters are more energy-efficient than non-condensing water heaters. Rinnai offers a hybrid condensing model with an 80-gallon storage tank, which Navien does not provide.

Navien’s condensing models have 0.96 UEF, while their non-condensing models are about 0.81 UEF. Their NPE-A2 and NPE-S2 Series are ENERGY STAR certified. Rinnai’s condensing models are between 0.85–0.93 UEF, while their non-condensing models are 0.79–0.83 UEF. Their SE+ Series is ENERGY STAR certified.


When you’re buying a new appliance, the warranty is essential to consider. Warranty periods differ for labor, parts, and heat exchangers.

Navien’s warranty for standard and controlled recirculation residential tankless water heaters:

  • Heat Exchanger: 15 years
  • Labor: 1 year
  • Parts: 5 years

Rinnai’s warranty period differs by series for residential applications

Rinnai Series                 Heat Exchanger    Labor     Parts
HE non-condensing      10 years                 1 year    5 years
HE+ non-condensing    12 years                 1 year    5 years
SE condensing              12 years                 1 year    5 years
SE+ condensing            15 years                 1 year    5 years

So, unless you buy the super-high-efficiency Rinnai model, you won’t get as long a warranty on the heat exchanger as you will with any Navien model.

Prices of On-Demand Water Heaters

Price is a significant factor for many homeowners when choosing a new appliance like a water heater. Though tankless on-demand water heaters are more expensive up front, they are incredibly efficient and longer-lasting, making up for the higher upfront cost.

Depending on the model and if your water heater runs on natural gas or propane, expect to pay between $700–$3,000 or more for a Navien or Rinnai tankless water heater.

You also must factor in professional installation costs because an on-demand water heater has a specialized installation process. Some savvy DIY homeowners can replace their storage tank water heater, saving on installation costs.

Installing Your Tankless On-Demand Hot Water Heater

Tankless water heaters are a great solution to endless hot water while still keeping your energy bills in check. If you’re ready to buy an on-demand water heater, contact the expert Severna Park plumbers at Abend Services for a professional installation appointment. Still not sure which brand is best? Give us a call, and we’ll help you find the best brand and solution for your household hot water needs.

Call (410) 618-3115


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