When you first turn on the tap, there is typically a delay in getting hot water, as the water in the pipes leading from the water heater to the tap will be cold.

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However, Canadian studies have shown, even when the thermostat is set at 60°C, a high percentage — approximately 40% — of electric water heaters remain contaminated.

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The Rinnai Smartstart® Water Saver was developed to reduce water wastage whenever a hot water is turned on.  It pre-heats the water in the pipes before you turn on the hot tap.

Tankless systems can also be set at 50ºC, so the risk of scalding is greatly reduced without the need of a tempering valve.

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This keeps the tank hot enough to stop bacterial growth (>60°C) and a lower tap temperature (≈50°C) to help reduce the risk of accidental scalding.

With tankless systems, the prevention of bacterial growth is not an issue, as there is no stored water in which bacteria can breed.

Steve Reynolds is a leading expert in the LPG industry with over 22 years of experience. As part of the national management team at ELGAS, Steve ensures the safe and efficient storage, handling, and transportation of LPG. He serves as the lead investigator for incidents and collaborates with authorities on industry developments.

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A hot water tempering valve or hot water tank mixing valve does this by mixing in cold water with your hot water, before it reaches your taps.

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A hot water tank mixing valve maintains a high tank temperature whilst simultaneously providing more tepid water for taps.

Because it is kept hot, tank systems can be slightly faster in delivering the initial flow of hot water, as the tankless system takes a second or two for the unit to get up to temperature.

We review the two hot water system types and compare the pros and cons of both, as well as the prices, to help you make an informed decision.

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Tempering valves have a temperature sensitive element which adjusts the mix depending on the temperature of the incoming water flowing through the valve.

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Steve is a technical advisor to Standards Australia and Gas Energy Australia (GEA), and an active member of the World LPG Association (WLPGA), contributing to global standards and technical reviews. He holds a BSc. (Hons) in Industrial Chemistry from UNSW and has held senior safety and technical roles at ELGAS, making him a trusted authority in LPG safety and standards.

Unless a minimum of 60°C is maintained, hot water tanks can be a breeding ground for Legionnaires’ disease, or Legionellosis, that is caused by a bacterium, Legionella pneumophila.  It is a respiratory disease that can cause severe pneumonia and is sometimes fatal.

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Tankless gas hot water systems only needs to run when the hot water is actually required and wasteful pilot lights are a thing of the past.

Mounted flush against the wall, the smaller tankless units take up less space and are also more aesthetically pleasing, as they don’t dominate the exterior appearance of your home.

Tankless gas hot water systems produce about 75% less CO2 greenhouse gas emissions, when compared to a storage tank hot water systems powered by coal-fired electricity.

There are different types of hot water tank mixing valve or hot water tempering valve for different types of hot water heaters.