Rinnai N1600i 58.4 kW Internal Natural Gas Water Heater | Low-NOx

Rinnai N1600i Natural Gas water heater

The Rinnai N1600i 58.4 kW Internal Natural Gas Water Heater is a commercial condensing continuous-flow water heating solution designed for professionally engineered hot-water systems.

Part of the Rinnai N Series, the N1600i combines condensing technology, automatic output variation, Low-NOx burner technology and a stainless-steel primary heat exchanger. Rinnai identifies the internal model as N1600i (REU-N3237FFC).

The N1600i is designed for internal installation and uses a forced room-sealed flue system, making it suitable for appropriate commercial plant-room installations when correctly specified and professionally installed.

Key Features

• Rinnai N1600i commercial water heater
• 58 kW-class gas water heater
• Natural Gas configuration
• Internal installation
• Condensing instantaneous operation
• Automatic output variation
• Low-NOx combustion technology
• Stainless-steel primary heat exchanger
• 13:1 turndown ratio
• Direct electronic ignition
• Forced room-sealed flue system
• Continuous-flow hot-water production
• Cascade capability
• Commercial high-demand hot-water applications
• Manufacturer model reference REU-N3237FFC

58.4 kW-Class Commercial Natural Gas Water Heater

The Rinnai N1600i is designed for commercial applications where a substantial and responsive supply of hot water is required.

Unlike a conventional storage water heater, the N1600i operates as a continuous-flow appliance, heating water as demand occurs.

Rinnai identifies the N1600i as a condensing instantaneous water heater with automatic output variation. The N1600 range is also specified at approximately 954 L/h at a 50°C temperature rise.

Actual hot-water performance depends on incoming water temperature, required outlet temperature, water pressure, gas supply and installation conditions.

Internal Installation

The N1600i is specifically designed for internal installation.

Rinnai’s technical documentation distinguishes the N1600i from the N1600e external model:

• N1600i: Internal installation
• N1600e: External installation

The N1600i uses a forced room-sealed flue system.

This configuration can be appropriate for commercial plant rooms and other suitable internal installations where the required gas, water, flue, electrical and condensate arrangements can be provided.

Natural Gas Commercial Water Heating

This EuroFuelSupply product is positioned specifically for Natural Gas applications.

Rinnai’s technical documentation includes G20 Natural Gas specifications for the N1600i. The exact gas supply requirements must be confirmed against the appliance documentation and the regulations applicable to the country of installation.

Before ordering, the installer should confirm:

• Natural Gas availability
• Gas pressure
• Gas supply capacity
• Appliance configuration
• Installation requirements
• Applicable local regulations

Low-NOx Technology

The N1600i incorporates Low-NOx combustion technology.

Rinnai’s current commercial documentation lists NOx emissions of approximately 26 mg/kWh for the N1600i.

Low-NOx performance is an important consideration when specifying commercial gas-fired water-heating equipment for projects subject to emissions requirements.

Condensing Technology

The N1600i is a condensing instantaneous water heater.

Its condensing design forms part of the appliance’s commercial hot-water system architecture, while automatic output variation allows the unit to respond to changing demand.

The actual efficiency of a complete installation depends on operating temperatures, system design, water demand and installation conditions.

Stainless-Steel Heat Exchanger

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

This component is designed for demanding commercial water-heating applications and forms part of the N Series’ continuous-flow system.

Automatic Output Variation

The N1600i is designed to vary its output according to hot-water demand.

This allows the appliance to respond to changing usage rather than simply operating continuously at maximum output.

Rinnai identifies automatic output variation as a defining feature of the N1600i.

13:1 Turndown Ratio

The N Series incorporates a 13:1 turndown ratio.

A high turndown ratio allows the appliance to modulate its operation over a broad demand range, which is particularly useful in commercial properties where hot-water requirements can vary throughout the day.

Continuous-Flow Hot Water

The N1600i provides hot water through a continuous-flow design rather than relying on a large integrated storage tank.

This makes it suitable for commercial applications where hot-water demand may fluctuate throughout operating hours.

Potential applications include:

• Hotels
• Restaurants
• Commercial kitchens
• Bars
• Gyms
• Leisure facilities
• Healthcare premises
• Food production
• Brewing
• Commercial accommodation
• Industrial facilities
• Agricultural businesses
• Other high-demand hot-water installations

The appliance should always be correctly sized for the actual project.

Commercial Cascade Systems

The Rinnai N Series can be configured in cascade systems for applications requiring greater hot-water capacity.

A cascade arrangement can allow multiple water heaters to work together as part of a larger commercial hot-water system.

This can be considered for projects with significant peak demand, including larger hospitality, leisure, healthcare and industrial facilities.

The required number of units should be determined through professional system design.

Direct Electronic Ignition

The N1600i uses direct electronic ignition.

This forms part of the appliance’s automatic operating system and works with the heater’s control and output modulation functions.

Forced Room-Sealed Flue

The N1600i uses a forced room-sealed flue system.

This is a key difference between the internal N1600i and external N1600e.

Rinnai specifies:

N1600i — Internal / Forced Room Sealed

N1600e — External / Direct Forced Exhaust

The flue arrangement must be designed and installed according to the current Rinnai installation instructions and the regulations applicable to the installation country.

Technical Specifications

Always confirm the exact technical specifications against the latest Rinnai documentation and appliance configuration before installation.

Rinnai N1600i vs N1600e

The N1600i and N1600e are closely related Rinnai N Series commercial water heaters, but they are designed for different installation environments.

Rinnai N1600i

• Internal installation
• Forced room-sealed flue
• Model reference REU-N3237FFC
• IPX4D
• Approx. 29 kg

Rinnai N1600e

• External installation
• Direct forced exhaust
• Model reference REU-N3237WC
• IPX5D
• Approx. 29 kg

Rinnai’s documentation clearly differentiates the two models.

Choose the N1600i when an internal installation is appropriate and the required room-sealed flue system can be provided.

European Commercial Applications

The Rinnai N1600i 58.4 kW Natural Gas Water Heater is suited to consideration for European commercial hot-water projects where Natural Gas continuous-flow heating is appropriate.

Its combination of:

• Internal installation
• Condensing operation
• Low-NOx technology
• Automatic output variation
• Stainless-steel heat exchanger
• 13:1 turndown
• Commercial capacity
• Cascade capability

makes it suitable for professionally designed high-demand hot-water systems.

EuroFuelSupply supplies heating, hot-water and energy products to customers across supported European markets.

For commercial developments, installers, developers and multi-unit projects, contact EuroFuelSupply for availability and project enquiries.

Professional Installation

The Rinnai N1600i is a commercial gas appliance.

Installation, commissioning and servicing must be carried out by appropriately qualified professionals.

Before purchasing, the project designer or installer should confirm:

• Natural Gas supply
• Gas pressure
• Gas supply capacity
• Peak hot-water demand
• Incoming cold-water temperature
• Required hot-water temperature
• Water pressure
• Flue arrangement
• Condensate drainage
• Internal plant-room requirements
• Electrical supply
• Applicable gas regulations
• Building regulations
• Cascade requirements

Do not attempt to install, modify, convert or commission the appliance without the appropriate professional qualifications.

Frequently Asked Questions

What is the Rinnai N1600i?

The Rinnai N1600i is an internal commercial condensing instantaneous gas water heater in the Rinnai N Series.

What is the Rinnai N1600i model number?

Rinnai’s technical documentation identifies the N1600i as REU-N3237FFC.

Is the Rinnai N1600i a Natural Gas water heater?

Yes. The N1600i documentation includes G20 Natural Gas specifications.

Is the Rinnai N1600i a Low-NOx water heater?

Yes. The N1600i uses Low-NOx combustion technology, with Rinnai’s current documentation listing approximately 26 mg/kWh NOx.

Is the N1600i an internal water heater?

Yes. Rinnai specifically identifies the N1600i as the internal model.

What is the N1600i flow rate?

Rinnai specifies approximately 954 L/h at a 50°C temperature rise for the N1600 range. Actual flow depends on operating conditions and system design.

Does the N1600i use a storage tank?

No. It is a continuous-flow/instantaneous water heater that heats water as demand occurs.

What type of flue does the N1600i use?

The N1600i uses a forced room-sealed flue system.

Can multiple N1600i units be used together?

Yes. The N Series supports cascade configurations for larger commercial hot-water requirements.

Is the N1600i suitable for hotels and restaurants?

It can be considered for professionally designed commercial hot-water systems in hotels, restaurants, commercial kitchens and other high-demand applications, provided the system is correctly sized.

Does the N1600i require professional installation?

Yes. Gas, water, flue, condensate and electrical work must be completed and commissioned by appropriately qualified professionals in accordance with the manufacturer’s instructions and local regulations.