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Rinnai Demand Duo System

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  • Same day shipping for stocked items
  • Money back guarantee
  • Outstanding service & expert technical advice
  • AU owned & operated for 50 years

Quick Overview

Rinnai Demand Duo systems are a combination of between 1 and 6 gas continuous flow Heavy Duty water heaters with a 250 or 315 litre heavily insulated storage tank. The storage tank allows a short period of high hot water flow rate, greater than the combined continuous flow rate of the HD water heater(s).

Each Complete Demand Duo Packaged System includes:

  • One or more Rinnai Heavy Duty Series Water Heaters
  • A Manifold System (where multiple HD Heaters are used)
  • Primary Pump(s)
  • Thermostat
  • 205 or 315 Litre Stainless Steel Storage Tank

The Thermostat starts the pump when the temperature drops below the required heat. This in turn fires off the HD Water heater(s).

Ideal Applications

Anywhere predictable a large regular volume of Hot Water is required for showering, washing or regular industrial processes.

  • Hotels and Motels
  • Apartment Blocks
  • Student Accomodation
  • Shower Blocks
  • Commercial Kitchens
  • Commercial Laundry

The Demand Duo is typically installed with flow and return systems to ensure that there is only a short wait for Hot Water anywhere in the building.


Demand Duo 4 HD Heaters


How to make your selection

When you Request-a-Quote the following information is required for us to select a suitable Demand Duo system for your project:

  • Temperature rise required. Assumed to be 50° (15 - 65°C)
  • Volume of hot water used per event (i.e. people having a shower)
  • Number of times this event occurs (i.e. 6 uses of each shower head per hour)
  • Internal or external installation (also determines whether a flue system is required)

Combinations Available:

  • Boosters available: HD200/HD211/HD250
  • Location: Internal and External
  • Number of boosters needed: 1 - 6
  • Natural Gas or LPG
  • Tank sizes: 250 or 315 litres
  • A Solar Pre-Heat option is also available

Contact G Store to find the correct Demand Duo System for your application

Additional Information:

Rinnai Commercial Hot Water Reference Guide

Additional Information

Energy Star Rating No


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Rinnai Demand Duo System 0 out of 1 5 based on ratings. user reviews.