Noritz NR71 
Tankless Water Heaters 
Review and Buying Tips

A review of the main features and benefits of Noritz NR71 tankless water heaters. When should you buy a Noritz water heater from the NR71 series? 

Noritz water heaters from the NR71 series (old N-0631S) are designed as tankless units for an endless and continuous hot water supply. They heat water on demand and supply up to three bathrooms or smaller and middle-size homes.

Tankless technology allows Noritz NR71 great flexibility so that they can be installed almost anywhere. They are wall-mounted with forced and sealed combustion, making them ideal for kitchen or bathroom installation and where the point of service is.


NoteProfessional installation and repair are recommended. Find local plumbers and get FREE Quotes!

Models review

The NR71 series consists of two models: Noritz NR71-SV model that can be installed either inside (with the correct venting) or outside, and a model Noritz NR71-OD, which can be installed outside only.

When used as an indoor model, a model NR71-SV uses a stainless steel pipe for horizontal or vertical venting, while the outdoor model has the horizontal vent built into the unit. They are made for residential and some commercial applications but are not built for recreation vehicles and boats.


Capacity and power

Both Noritz NR71 water heaters are designed to provide the maximum power of 180,000 BTU and water flow of 7.1 gallons per minute (at 35 F temperature rise), which makes them ideal for supplying hot water up to three applications at the same time.

If you need just a trickle of water for face washing or shaving, NR71 models can lower the water flow to its minimum of 0.5 GPM, where power, thanks to the modulating burner, will also be reduced to its minimum of 25,000 Btu/hr.

Single powerful burner

These models come with one single burner, which is very efficient and provides stable water temperature while reducing greenhouse gas emissions.

Efficient heating

Direct electronic ignition is the standard equipment, so no more waste of energy through the pilot light. It also contributes to keeping the energy factor high, which is above 0.82.

Self-diagnostic system

If something is wrong with the unit, the self-diagnostic computer system shows the error message (11, 90, 99...) on the remote control (not supplied with the unit), and based on the code; you can easily troubleshoot the problem. If not using the remote control, check for flashing on the unit as the lamp diode displays the error.

Remote control

Also, if using the remote control, it is easy to change the temperature of the outgoing hot water, and there are 12 options where the minimum temperature is 100 F while the maximum is 160 F.

Safety features

´╗┐Both indoor and outdoor NR71 models are equipped with the safety features to protect the water heater, you, and your home:

  • Flame rod
  • Automatic overheat protection system - Thermal fuse
  • Overheat prevention system
  • Freeze protection to - 30 F for indoor and -4 F for outdoor models. This applies to the heater's internal plumbing.
  • Lighting protection device
  • Fan rotation detector
  • Safety lock-out system to protect from scalding temperatures.
  • Resin coated PC board protect the elements and makes them durable.


NR71 tankless water heaters used for residential water heating come with a 12-year limited warranty on the heat exchanger, 5 years on other components, and one year on labor.


Noritz NR71 water heaters are, with tankless technology, ideal for homes with up to three bathrooms or to supply three applications with hot water simultaneously. Being Energy Star compliant, NR71 models provide lower water heating costs and rebates from utility companies, including government grants, when available. Both models are made of strong materials, which make them very durable and reliable.


Leave a Comment

[ ? ]

Author Information (optional)

Submit Your Contribution

  •  submission guidelines.

(You can preview and edit on the next page)