Rinnai N1600i 58 kW Internal Condensing Gas Water Heater

The Rinnai N1600i internal condensing gas water heater is a high-output commercial continuous-flow water heating solution designed for buildings with demanding and variable hot-water requirements.

The N1600i is part of the Rinnai N Series commercial water heater range and is designed for internal installation. Rinnai classifies the N1600i as a 58 kW commercial tankless water heater, with performance of up to 954 litres per hour at a 50°C temperature rise.

Unlike a conventional storage water heater, the N1600i heats water continuously as demand occurs. This makes it suitable for commercial properties where hot-water demand can change throughout the day.

Key Features

• Rinnai N1600i internal commercial gas water heater
• 58 kW-class high-output performance
• Up to 954 L/h at a 50°C temperature rise
• Up to 37 L/min under specified operating conditions
• Condensing instantaneous water heating
• Stainless-steel primary heat exchanger
• Low-NOx burner technology
• 13:1 turndown ratio
• Automatic output modulation
• Internal installation
• Forced room-sealed flue system
• Direct electronic ignition
• Built-in controls
• Cascade capability
• Suitable for commercial continuous-flow hot water applications
• Hydrogen-blend and BioLPG-ready N Series technology, subject to applicable fuel and installation requirements

Rinnai confirms the N Series uses stainless-steel heat exchangers, Low-NOx burner technology and a 13:1 turndown ratio. Multiple units can also be cascaded for larger hot-water requirements.

High-Output 58 kW Commercial Water Heater

The Rinnai N1600i 58 kW gas water heater is designed for commercial installations requiring substantial quantities of temperature-controlled hot water.

Rinnai lists the N1600i at 954 litres per hour at a 50°C temperature rise. The manufacturer also states that the N1600 can produce up to 37 litres per minute, with actual flow depending on operating conditions, temperature setting and incoming water temperature.

For this reason, the 954 L/h figure should be used when comparing standardized temperature-rise performance, while the litres-per-minute figure should always be considered alongside the required temperature rise.

Continuous-Flow Commercial Hot Water

The N1600i uses a continuous-flow design rather than relying on a large integrated storage tank.

Water is heated as it passes through the appliance, allowing the system to respond to changing demand.

This configuration can be particularly useful for:

• Hotels
• Restaurants
• Commercial kitchens
• Sports centres
• Gyms
• Leisure facilities
• Care homes
• Schools
• Apartment developments
• Holiday accommodation
• Industrial buildings
• Commercial washrooms
• Healthcare facilities

Correct sizing should be based on peak flow requirements, incoming water temperature, required outlet temperature and the site’s expected hot-water demand.

Stainless-Steel Heat Exchanger

The Rinnai N Series uses a stainless-steel primary heat exchanger.

Rinnai describes this construction as a core feature of its N Series commercial continuous-flow water heaters, designed to support durability and performance in demanding applications.

13:1 Turndown Ratio

The N1600i incorporates a 13:1 turndown ratio.

The appliance can therefore modulate its gas input according to changing hot-water demand rather than operating continuously at maximum output.

Rinnai identifies the 13:1 turndown as a key feature of the N Series.

Low-NOx Gas Burner

The N1600i incorporates Low-NOx burner technology.

Rinnai’s current N Series documentation highlights advanced burner technology designed for continuous-flow commercial water heating. The manufacturer’s technical documentation lists NOx emissions of approximately 27.4 mg/kWh for the N1600i configuration.

Internal Installation

The N1600i is designed for internal installation.

Rinnai identifies the appliance installation type as internal and specifies a forced room-sealed flue system.

The appliance is suitable for wall mounting, while Rinnai also provides cascade installation options where additional units are required.

Flue routing, combustion air, condensate drainage, gas supply, clearances and commissioning must be completed according to the manufacturer’s installation requirements and applicable local regulations.

Continuous Hot Water Without a Large Storage Tank

The N1600i is a condensing instantaneous water heater, rather than a conventional storage-cylinder system.

This makes it appropriate for commercial sites where demand varies considerably and where continuous-flow hot water is preferred.

The appliance’s automatic output variation allows its gas input to respond to demand.

Cascade Commercial Water Heating

One of the major advantages of the Rinnai N Series is its ability to operate in cascade configurations.

Multiple Rinnai water heaters can be connected to work as a larger commercial hot-water system.

Rinnai states that N Series units can be cascaded to supply very high hot-water demand, while its published case-study material notes that up to 24 units can be connected in an appropriate cascade arrangement.

This makes the N1600i suitable for projects where a single water heater is insufficient.

Natural Gas and LPG Configurations

The N1600i product family supports applicable gas configurations, including natural gas and LPG-related configurations depending on the market and appliance setup.

The exact gas type, conversion procedure, gas pressure and installation requirements must always be confirmed against the manufacturer’s documentation for the selected configuration.

Do not describe the N1600i as a simultaneous dual-fuel appliance.

Hydrogen-Blend and BioLPG Ready Technology

Rinnai states that its N Series commercial water heaters are 20% hydrogen-blend ready and BioLPG ready, subject to the applicable fuel supply and installation conditions.

This technology is particularly relevant for European commercial heating projects where gas infrastructure and fuel specifications are evolving.

Technical Specifications

Rinnai’s current technical documentation confirms the internal installation, forced room-sealed flue, 13:1 turndown, 29 kg weight, 59 dB(A) noise level, 230 V/50 Hz supply and the N1600i reference REU-N3237FFC.

Rinnai N1600i vs N1600e

The N1600i and N1600e are both high-output Rinnai N Series commercial water heaters.

The key difference is installation:

N1600i

• Internal installation
• Forced room-sealed flue
• Suitable where the water heater is installed inside the building

N1600e

• External installation
• Designed for outdoor mounting
• Different flue arrangement

Both N1600 versions are listed by Rinnai at 954 L/h at a 50°C temperature rise.

Rinnai N1600i vs N1300i

The N1600i is the higher-capacity internal model in the N Series.

Rinnai lists the N1600i at 954 L/h, compared with 775 L/h for the N1300i at a 50°C temperature rise. The N1600 models also have an XXL load profile, while the N1300 models have an XL load profile.

For larger commercial hot-water requirements, the N1600i provides the higher-capacity option.

Is the Rinnai N1600i Suitable for Commercial Buildings?

Yes. Rinnai specifically positions the N1600i as a commercial continuous-flow gas water heater.

Its high output, continuous-flow operation, stainless-steel heat exchanger, Low-NOx burner, modulation and cascade capability make it suitable for demanding commercial hot-water applications.

Does the Rinnai N1600i Have a Storage Tank?

No. The N1600i is a condensing instantaneous water heater.

It heats water as demand occurs rather than storing a large volume of hot water in an integrated storage tank.

How Much Hot Water Does the N1600i Produce?

Rinnai specifies the N1600i at up to 954 litres per hour at a 50°C temperature rise.

Rinnai also states that the N1600 can produce up to 37 litres per minute, although actual flow depends on temperature setting and incoming water conditions.

Can Multiple N1600i Water Heaters Be Connected?

Yes. The N Series supports cascade installations.

Multiple units can be connected to increase overall hot-water capacity for larger commercial projects.

What Is the Manufacturer Reference for the N1600i?

Rinnai’s current technical documentation identifies the internal N1600i as REU-N3237FFC, while the product fiche identifies REU-N3237FFC-E. When ordering, the exact manufacturer reference and regional configuration should be confirmed against the current Rinnai documentation.

Is Professional Installation Required?

Yes.

The N1600i is a commercial gas-fired appliance and must be installed, commissioned and serviced by appropriately qualified professionals.

Gas supply, flue installation, condensate drainage, electrical connections, water pressure and commissioning must comply with the applicable regulations in the country of installation.

Buy Rinnai N1600i in Europe

The Rinnai N1600i 58 kW internal condensing gas water heater is designed for commercial properties requiring high-volume, temperature-controlled hot water.

For European projects, select the correct gas configuration and installation arrangement based on the site’s water demand, temperature rise, incoming water conditions and applicable national requirements.

Contact EuroFuelSupply for product availability, commercial quantities, accessories and European delivery options.