Rinnai INFINITY® HD250 external

Commercial water heating at its best


**The model has replaced by the HD56kWe**

The Rinnai INFINITY HD250 is a higher capacity gas continuous flow water heater for applications where higher flow rates and higher temperatures are needed. The HD250 model can be set up to 95 °C.

Suitable for
• external commercial and residential applications
• mains and medium pressure systems

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

Not suitable as a spa or swimming pool heater, or for hydronic applications.

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Technical Specifications



Preset temp.

55 °C




29 kg

Gas type

Available for Natural Gas or LPG, specify at the time of purchase

Codes and REU numbers
  • REU number: REU-VR3237WG
  • Code NG: INFHD250HNCN
  • Code LPG: INFHD250HNCL
Hot water capacity

2.4-37 L/min, nominal water capacity is 32 L/min at a 25 °C rise (1920 L/h)

Input and output

Input: 249 MJ/h or 69 kW
Output: 57.8 kW

Hot water connections
  • Hot water outlet R¾ (20 mm)
  • Cold water inlet R¾ (20 mm)
  • Gas supply R¾ (20 mm) 
Ignition system

Direct electronic ignition

Exhaust system

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.

Injector sizes

NG: 1.00, 1.65
LPG: 0.75, 1.15

Ingress protection rating


Line pressure (min.)

NG - 1.13kPa, 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.

Noise level

59 dB(A). Some people are susceptible to low level noise. This needs to be considered if locating an appliance near a bedroom.

NOx af

less than 60 ppm

Power consumption

Normal 72 W, automatic frost protection 116 W, standby 2 W

Pressure relief

Valve opens at 2060 kPa, closes at 1470 kPa

Safety devices
  • Flame failure
  • Boil-dry protection
  • Overheat protection
  • Fusible link
  • Pressure relief valve
  • Combustion fan RPM check
Water supply
  • Nominal operating pressure: 200-1000 kPa
  • Activation flow rate: 2.4 litres per minute

Please note: If the water inlet 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.


Energy Safety Supplier Declaration of Compliance declaration number: 10996200911

Market release

First launched 2010 and then relaunched in 2011

Last sold

Feb 2023


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