Rinnai INFINITY HD56K – External Gas Continuous Flow Hot Water Heater

Natural Gas or LPG | Commercial & Residential | 56 kW Output

All genuine Rinnai accessories for this unit are available to order on request.

The Rinnai INFINITY HD56K is a high-performance, external continuous-flow hot water system designed for large homes, commercial buildings, and high-demand applications. With up to 37 L/min of hot water and a powerful 56 kW output, it delivers reliable, on-demand hot water for multiple simultaneous outlets.

Available in Natural Gas or LPG (specify at purchase).

✔️ Suitable For

• External commercial and residential installations

• Mains and medium-pressure water systems

• Areas with treated hard or acidic water

✖️ Not Suitable For

• Spa or swimming pool heating

• Hydronic or central-heating applications

Replaces

• Rinnai INFINITY HD250 External model

Technical Specifications

Performance

• Input: 20.1–250 MJ/h (NG)

• Input (LPG): 20.1–245 MJ/h

• Output: 56.4–56.8 kW

• Thermal Efficiency: 82%

• Preset Temperature: 50 °C

• Hot Water Capacity: 1.5–37 L/min

• Nominal Flow: 32 L/min @ 25°C rise (1920 L/h)

Gas Type

• Available in Natural Gas or LPG

• Specify gas type when ordering

Colour

• Silver

Model Codes

• INFHD56N – Natural Gas

• INFHD56L – LPG

• REU Number: REU-AM3237WC-ZK

Connections

• Hot Water Outlet: R ¾ (20 mm)

• Cold Water Inlet: R ¾ (20 mm)

• Gas Supply: R ¾ (20 mm)

Operating Details

• Exhaust System: Forced flue

• Ignition: Direct electronic ignition

• Ingress Rating: IPX5

• Noise Level: 55 dB(A)

• Normal Power Use: 87 W

• Standby: 2 W

• Frost Protection Mode: 88 W

Water Supply Requirements

• Operating pressure: 200–1000 kPa

• Minimum flow depends on temperature setting and inlet temperature

Line Pressures

• NG: 1.13–3.0 kPa

• LPG: 2.75–3.0 kPa

• Maximum: 3.5 kPa (5.0 kPa allowable under abnormal intermittent conditions)

• Commercial installations with 35–37 kPa incoming pressure may require regulation.

Frost Protection

Fitted as standard. Activates automatically when internal temperature drops below 3.5 °C and switches off once the unit reaches 7 °C.
Requires the appliance to remain connected to mains power.

Safety Features

• Flame-failure protection

• Boil-dry protection

• Overheat safety (OHS)

• Fusible link

• Pressure relief valve

• Combustion-fan RPM check

Dimensions & Weight

• Weight: 23 kg

• Dimensions: (Include if you want these added — happy to insert them.)

Compliance

• Supplier Declaration of Compliance: DEC-000002250L2L2

• Market release: January 2023

All genuine Rinnai accessories for this unit are available to order on request.