Flat Plate systems

Flat Plate Solar Systems consist of a ground mounted storage tank that is installed separately to the collectors mounted on the roof. A solar control unit ensures water circulates between the tank and collectors.

Cost effective Vitreous Enamel tanks

Highly efficient aluminium fin solar collectors

Collectors and tank can be installed separately

  • A range of storage capacities from 175 litres to 315 litres
  • Available with electric boost or continuous flow gas boost
  • Minimal impact on the aesthetics of your roofline
  • No need to reinforce the roof structure
  • Enduro collectors use aluminium fin solar absorber to maximise efficiency
  • Innovative control system using a stepless speed controlled pump
  • A sacrificial anode is provided in the tank for added protection
  • Suitable for high wind areas to classification region D in accordance with AS/NZS1170.2:2011 using our additional cyclone frame
  • Warranty is 10 years on the tanks and 7 years on the collectors


Storage capacity Booster No Of
Enduro Collectors
No of Bedrooms
System 1 175L S20 1 1 to 3
System 2 175L S26 1 2 to 3
System 3 215L S20 2 2 to 3
System 4 215L S26 2 3 to 4
System 5-SL 270L S26 2 3 or more
System 6-SL 250L 3.6 kW 2 1 to 3
System 7-SL 315L 3.6 kW 2 3 to 4
System 8-SL 315L 3.6 kW 3 3 or more

Contact your local Rinnai Solar Specialist for more information.


  • What is a solar hot water system?

    What is a solar hot water system?

    A typical solar hot water system is made up of solar collectors, a storage tank, a gas or electric booster and a solar controller and pump for split systems.

    There are two types of systems available

    1. Close Coupled systems
    2. Split systems

    Close Coupled systems have the storage tank above the solar collectors all located together on the roof. Close Coupled systems rely on thermosyphon to operate: cold water from the bottom of the tank falls to the inlet at the bottom of the solar collectors. The water is heated by the sun, rising up through the solar collector and back into the middle and top of the tank.

    Split systems have the storage cylinder located on the ground and the solar collectors located on the roof. Split systems use a solar controller and pump to transfer cold water from the tank to the solar collectors to be heated and returned to the middle or top of the tank. The solar controller compares the temperature of the water in the solar collector to that in the tank. When the collector is hotter than the tank the pump is switched on, transferring the solar heated water to the tank.

  • Why use a solar (thermal) hot water system?

    Why use a solar (thermal) hot water system?

    Installing a solar hot water system has great benefits especially when replacing an electric storage tank. It can potentially reduce electricity consumption, running costs and environmental impact by 2/3rds.

    40% of a typical households electricity is used for heating water. Therefore a solar water heater can potentially reduce the overall electricity use by 25%.

    Australian electricity is predominantly generated using non renewable and dirty coal fired power stations. As well as electricity they produce carbon dioxide emissions, ash, particles and waste heat, while consuming vast quantities of water and non renewable coal.

    Rinnai solar hot water systems reduce the need for electricity and are part of many major energy reduction programs. Solar hot water systems also offset electricity just when it is needed most: Summer - as that is when air conditioners are running, loading up the electricity network.

  • Will I get solar gain in winter?

    Will I get solar gain in winter?

    Solar gain is available during the day throughout the year. Even cloudy days can deliver some solar gain. A clear winter day may sometimes deliver more solar energy than a cloudy summer day.

    • Clear and sunny days produce high solar contirbution
    • Clear and cold days produce reasonable solar constirbution
    • Overcast and warm day produce reasonable solar contribution
    • Overcast and cold days produce low solar contribution
  • How do I size a solar hot water system?

    How do I size a solar hot water system?

    The storage tank should hold a one days supply of hot water and have enough capacity to store the amount of solar energy collected by the solar collectors. Once the tank size is chosen to match household hot water use, the number of solar collectors is matched to the tank.

    For help with selection contact one of our licensed dealers or alternatively visit our store locator.

  • What is a solar collector?

    What is a solar collector?

    The solar collector is the most important component within the system as it absorbs the energy from the Sun and heats the water. Collectors are generally made up of a combination of:-

    • A glass surface (flat on a flat plate collector or round for evacuated tube collectors)
    • Tubes containing a fluid that is to be heated by solar energy
    • Heat absorbing surface / fins attached to the tubes
    • A treated surface on the absorber to capture and retain solar radiation
    • A casing / vacuum to retain heat
    • Pipework to enable the transfer of solar energy to the storage tank

    The solar collectors are roof mounted and ideally face North when installed in Australia. Facing East or preferably West is OK, but a reduced amount of solar energy will be collected.

    Avoid having the collectors shaded by adjacent buildings, structures and trees.

  • What is the difference between Solar Thermal Collectors and PV Panels?

    What is the difference between Solar Thermal Collectors and PV Panels?

    They are separate solar energy collection technologies.

    • Solar (thermal) hot water systems convert radiant energy into hot water.
    • Photovoltaic (PV) solar converts radiant energy into electricity.
  • Why do I need a booster for my solar system and what types are available?

    Why do I need a booster for my solar system and what types are available?

    A booster is required to deliver hot water in times of low solar contribution or times of excessive hot water consumption.

    There are 2 booster options available:

    • Gas
    • Electric


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