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Non-Condensing Tankless Water Heaters

A high-efficiency, space-saving technology that can supply endless domestic hot water for residential applications. Unlike bulky tank water heaters that continuously reheat water, wasting energy.

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Non-Condensing Products

How Non-Condensing Tankless Water Heaters Work

High-efficiency non-condensing tankless units only heat water when you want it, unlike wasteful tank water heaters. In simple terms, cold water travels through one heat exchanger supplying endless hot water to the fixtures in your home. When you upgrade to a tankless water heater, you can save energy and money.

  1. When a hot water tap is opened, the tankless water heater detects the flow

  2. The flow sensor activates to determine the amount of hot water needed

  3. The igniter activates

  4. The gas control valve opens to supply the correct amount of gas

  5. The burner ignites providing a flame to heat the water

  6. Cold water passes through the heat exchanger

  7. The unit determines outgoing set temperature and adjusts the flame to heat the water

  8. Desired hot water amount delivered to the faucet

  1. When a hot water tap is opened, the tankless water heater detects the flow

  2. The flow sensor activates to determine the amount of hot water needed

  3. The igniter activates

  4. The gas control valve opens to supply the correct amount of gas

  5. The burner ignites providing a flame to heat the water

  6. Cold water passes through the heat exchanger

  7. The unit determines outgoing set temperature and adjusts the flame to heat the water

  8. Desired hot water amount delivered to the faucet

What’s the difference between non-condensing & condensing tankless water heaters?

The design of a non-condensing water heater or boiler is to have a heat exchanger that transfers enough heat to get the water temperature where it is needed, but not to lower the exhaust gas temperature to a point where the water vapor condenses. Navien non-condensing gas tankless water heaters are built with a single, or primary, heat exchanger and require exhaust systems that will tolerate higher temperatures.

A condensing tankless water heater changes the design of the heat exchanger to take advantage of the water vapor in the exhaust gas. Navien condensing gas tankless water heaters include a second heat exchanger in order to transfer more heat to the water and lower the exhaust gas temperature to a point where the water vapor condenses inside the heat exchanger, increasing the flow rates and overall efficiency of the water heater. Since the exhaust gases are much cooler when they leave the heat exchanger, the exhaust system can be made up of a wider range of materials, such as Polypropylene or PVC. Because the water vapor from the burner is condensing inside the heat exchanger the installation also requires a drain to dispose of the condensation that is produced.

Are non-condensing tankless water heaters better than condensing? 

It depends, non-condensing tankless water heaters are smaller in design and don’t have to drain acidic condensate, which makes them more flexible when it comes to installation location. With an efficiency rating of 0.81 UEF, it is still much more efficient than a standard tank-type water heater.

Condensing tankless water heaters offer higher flow rates, an efficiency rating of up to 0.96 UEF, and the lower exhaust temperatures allow them to use more cost-effective installation materials such as polypropylene or PVC. Condensing units do need to drain out acidic condensate, so they will require a condensate drain and potentially a condensate neutralizer to neutralize the pH of the condensate before it is drained.

Condensing vs Non-Condensing Tankless Water Heaters

  Condensing Non-Condensing
Initial cost Usually higher than comparable non-condensing Usually lower than comparable condensing
Long term operating cost Lower than typical non-condensing tankless and storage tank system Could be higher than condensing but lower than storage tank systems
Efficiency Ultra-high Efficiency (UEF up to .96) High Efficiency (UEF > .80)
Maintenance requirement Annual service recommended Minimal
Venting PVC acceptable 3" x 5" metal concentric required
Installation Location Indoor or Outdoor Choice of interior or exterior
Durability Stainless steel heat exchanger extend service life Stainless steel heat exchanger extend service life
Dimensions Slightly larger than non-condensing, about 70-80% smaller than tank system Slightly smaller than condensing, 80% smaller than tank system

Navien Non-Condensing Tankless Water Heaters

 

The Navien NPN series is a line of indoor/outdoor non-condensing tankless water heaters. These tankless water heaters typically have a longer lifespan than condensing models and require less maintenance.

Navien NPN Premium Non-Condensing Tankless Water Heaters

Introducing The New NPN Series

NPN-U Series

Universal premium non-condensing tankless water heaters for indoor/outdoor installations.

NPN-160U
Max DHW Input: 160,000 BTU/h
Indoor or outdoor wall-hung
Residential/Commercial
NPN-160U
View model
NPN-160U
NPN-180U
Max DHW Input: 180,000 BTU/h
Indoor or outdoor wall-hung
Residential/Commercial
NPN-180U
View model
NPN-180U
NPN-199U
Max DHW Input: 199,900 BTU/h
Indoor or outdoor wall-hung
Residential/Commercial
NPN-199U
View model
NPN-199U

NPN-E Series

Non-condensing tankless water heaters for outdoor installations.

NPN-120E
Max DHW Input: 120,000 BTU/h
Outdoor wall-hung
Residential/Commercial
NPN-120E
View model
NPN-120E
NPN-160E
Max DHW Input: 160,000 BTU/h
Outdoor wall-hung
Residential/Commercial
NPN-160E
View model
NPN-160E
NPN-180E
Max DHW Input: 180,000 BTU/h
Outdoor wall-hung
Residential/Commercial
NPN-180E
View model
NPN-180E
NPN-199E
Max DHW Input: 199,900 BTU/h
Outdoor wall-hung
Residential/Commercial
NPN-199E
View model
NPN-199E

Compare our advantages to other non-condensing tankless water heaters

Exclusive Navien NPN-Universal indoor or outdoor unit and NPN-Exterior dedicated outdoor unit. NPN-E outdoor models also feature remote control and built-in button controls for easy service. 

  • NPN tankless water heaters burner

    Navitech™ exclusive stainless steel heat exchanger.

    NPN series are the first and only non condensing tankless water heaters with a stainless steel heat exchanger to deliver unmatched durability and performance.

  • NPN tankless water heaters heat exchanger

    Navitech™ stainless steel burner.

    Designed and manufactured by Navien to burn gas at higher efficiency than other system on the market.

  • NPN tankless water heaters cascade

    Cascading capability.

    For increased domestic hot water flow demand, the NPN can be cascaded with another NPN unit.

  • NPN tankless water heaters NaviLink

    NaviLink™ Wi-Fi remote control.

    This optional accessory enables you to control temperatures remotely, access usage data and receive diagnostic notifications from your smart phone or tablet.

  • NPN tankless water heaters sleek design

    Space saving and lighter weight design.

    These sleek wall-hung units use much less space and are substantially lighter than traditional tank water heaters and other non-condensing tankless water heaters.

  • NPN tankless water heaters closet

    Low noise levels.

    Installations in or near media rooms, recreation rooms or any living areas of the house are possible with the quiet running NPN tankless water heaters.

Lower energy bills, easier on the planet

 
Unlike systems that waste energy to heat large tanks of water, Navien NPN series tankless units utilize 82¢ of every $1 to heat your water. NPN only fires up when hot water is needed, allowing great utility savings and a lower impact on the environment.

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