Rinnai INFINITY N-Series gas continuous flow water heaters

Super efficient, super smart
RRP $3,525

Rinnai INFINITY N-Series gas continuous flow water heaters

The Rinnai INFINITY N-Series are condensing* gas continuous flow water heaters designed for commercial applications and high hot water demand residential installations.

Available as an external unit (N56kWe) or an internal unit (N56kWi).


  • Full stainless steel heat exchanger and internal piping
  • Inverted burner → longer service intervals (burner cleaning no longer required)
  • Inbuilt control panel, parameters easily set
  • Pump connectivity, the N-Series can power and control a circulating ring main
  • Inbuilt temperature sensor, unit can run in-series with a circulating ring main
  • Pre-mix burner, no gas pressure setting required → very easy gas-type conversion
  • Daisy-chain electronic connection, very simple (and low cost) electronic connections
  • Powerful fan allows a lower cost common flue to be installed (available ex-stock) 

Suitable for
- External commercial and residential applications (N56kWe external model only)
- Internal commercial and residential applications (N56kWi internal model only)
- Mains and medium pressure systems

Hard or acidic water will need to be treated to use this product.

  • They are not suitable as a spa or swimming pool heater
  • They are not suitable for hydronic applications

Operating noise
Some people are susceptible to low level noise. INFINITY units operate at around 50-54 dB(A). This needs to be considered if locating the appliance near a bedroom.

Gas type
Available for Natural Gas or LPG. Specify gas type at the time of purchase.

General clearances for the external N56kWe
The following diagram has been provided to assist you in determining where (and if) an external N56kWe can positioned. If in doubt, prior to purchase, consult a licensed gasfitter.

N56kWe general clearances diagram and table

• Below eaves, balconies, and other projections, min. 300 mm
• From a gas meter 1000 mm
• From an electricity meter or fuse box, min 500 mm
* Rinnai recommend 1.5 m to give enough clearance for pipe work, and to safely expel flue gases

General clearances for the internal N56kWi
Internal models are designed for indoor installations only. They are a flued appliance. They may be installed in an enclosure if the requirements of AS/NZS 5601.1 are met. An enclosure is defined as a compartment, enclosed area, or partitioned off space primarily used for the installation of the appliance.

For internal units we recommend a 600 mm clearance in front of the unit for servicing access. This can be reduced to 50 mm if installed in a cupboard, refer diagram below.

internal clearances diagram



16-209 MJ/h


55.5 kW



Factory preset temp.

55 °C* (can be preset to deliver up to 85 °C**)

* Models manufactured before May 2020, serial number before 20.05-000001 were preset to 75 °C

** Maximum temp. for circulating systems is 65 °C
N56kWe (ext) code/REU INFN56N/L → REU-N3237WC-ZK
N56kWi (int) code/REU INFN56FFN/L → REU-N3237FFC-ZK
Hot water capacity 1.5-37 litres per minute. Nominal water capacity is 32 litres per minute at a 25°C rise (1920 L/h)
Exhaust system

External unit → forced flue

Internal unit → room sealed forced flue

Frost protection Fitted as standard. Frost protection operates automatically, as long as the appliance is connected to the electrical power supply, by activating when the temperature inside the unit drops below 3.5 °C, and turns off once the temperature inside the unit reaches 7 °C.
Ignition system Direct electronic ignition
Ingress protection rating IPX5
Line pressure (min.) NG: 1.13 kPa, LPG 2.75 kPa
Line pressure (max.) 3.5 kPa (maximum standing pressure under abnormal intermittent conditions is 5.0 kPa).

In the case of commercial metering, (i.e. 35-37 kPa coming in), there may be a requirement to regulate the incoming pressure down).
Power consumption

Normal: 70 W (NG), 85 W (LPG)

Standby: 2.4 W

Automatic Frost Protection: 154 W (external), 150 W (internal)

Water supply

Nominal operating pressure: 300-1000 kPa

Min. water flow: 1.5 litres per minute (activation flow rate)

Please note
If the inlet water pressure or flow rate drops below the minimum values stated above, operation of the INFINITY is not guaranteed. The unit requires both minimum flow rate and pressure to operate correctly.

Noise level Internal 49 dB(A), external 54 dB(A)
NOx af less than 50 ppm
Flue combustion analysis CO/CO² for nominal conditions:
- NG maximum load 144 ppm / 9.4%
- LPG maximum load 95 ppm / 10.1%
Safety devices Flame failure, boil-dry protection, overheat protection, fusible link, pressure relief valve and combustion fan rpm check

29 kg


ES: Supplier Declaration of Compliance

Declaration number: 1911920196

Market release January 2020
Q&A 1 Can an N-Series be used to replaced an older unserviceable Rinnai INFINITY in a bank of electronically connected appliances? Yes, as long as the N-Series is a slave unit and not the master. Refer attached for more information.

N56kWe (external) dimensions

N56 external dimensions line drawing

N56kWi (internal) dimensions

N56kWi internal dimensions line drawing


Bathroom Deluxe Controller

Bathroom Deluxe Controller
Will run a bath for you, turn off the water, then tell you when it's ready. Adjust the water volume of the bath or shower, temperature and the volume of the voice.

Compact Controller (MC601A)

Compact Controller (MC601A)
Our smallest most affordable model. This controller can be installed anywhere in the house.

Kitchen Deluxe Controller

Kitchen Deluxe Controller
Designed for kitchens and laundries, works in conjunction with the Bathroom Deluxe Controller. The voice will tell you in the kitchen when your bath is ready.

N56kWi flue diverter (FFP100DIV)

N56kWi flue diverter (FFP100DIV)
The N56kWi internal flue diverter (black UV resistant PVC) is a flue accessory kit that allows you to move the flue terminal position up and away from the air intake by up to 1.5 m.

N-Series cascades cable connection 3 m (REUCSAC1)

N-Series cascades cable connection 3 m (REUCSAC1)
With the use if the cascades cable connection(s), up to 24 N-Series water heaters can be electronically connected.

N-Series pump cable connection (R1071)

N-Series pump cable connection (R1071)
The N-Series 2 m pump cable will control a circulation pump in a ring main application.

Rinnai INFINITY® Error Indication Switch

Rinnai INFINITY® Error Indication Switch
Volt-free, normally open or normally closed switch. The switch will shift to the reverse position when there is an active error in the water heater. The switch is intended to be connected to a monitoring system such as a building management system.

Rinnai INFINITY® Pipe Cover

Rinnai INFINITY® Pipe Cover
A Rinnai pipe cover is available for a streamlined appearance, or to add additional protection in exposed installations.

Rinnai INFINITY® Security Bracket

Rinnai INFINITY® Security Bracket
A sturdy security bracket can be installed to act as a permanent deterrent against theft.
* Condensing technology utilises a secondary heat exchanger to drive further thermal efficiency by extracting heat from combusted flue gases, making the N-Series models 97% efficient.

Ducted Gas Heating Service Centre

Ducted Gas Heating Service Centre
Operating 5 days a week, 8am to 5pm, Monday to Friday our New Zealand based customer service centre provides nothing but top quality. If you need to book in a Ducted Gas Heating service, we have a team of providers fully trained and equipped with diagnostic tools to service your appliance when you need them. 

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