How the Sanden Heat Pump Works

Choosing a hot water system? Discover the Sanden Eco® Plus Hot Water Heat Pump System

How does the Sanden Eco® Plus Hot Water Heat Pump System work?

View the Sanden Hot Water Heat Pump Product Brochure

The Sanden Eco® Plus Hot Water Heat Pump System works in a different way compared to a conventional electric hot water system – it operates like a refrigerator in reverse.

The Sanden Eco® Plus uses a small amount of energy to move heat from one location to another. Heat is absorbed by ozone-friendly R744 (CO2), a natural refrigerant which does not contribute to global warming.

As the warm gaseous refrigerant circulates through the system, it passes through the compressor and its pressure and temperature rises. The hot refrigerant then passes through a heat exchanger which heats the water. The refrigerant is cycled back into the system, and hot water is pumped to the storage tank.

How Heat Pump Hot Water Systems Work

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Why employ R744 (CO2) refrigerant?
  • It offers no ozone layer depletion and minimal global warming (ie. as per table below) versus other commonly used refrigerants, should the system leak.
  • It performs higher compression efficiency, with lower energy consumption, thereby allowing more heat to be transferred to the water, for less energy used (i.e. excellent thermodynamic ability).
  • The refrigerant temperature gets very hot, very quickly, so water temperature of 63oC, is achieved almost instantly from the Heat Pump unit.
  • Sanden is the only currently available Hot Water Heat Pump in Australia to employ “ozone friendly” R744 (CO2) refrigerant.

* Global warming potential (GWP) is a measure of how much a given mass of greenhouse gas is estimated to contribute to global warming. It is a relative scale which compares the gas in question to that of the same mass of carbon dioxide (whose GWP is by convention equal to 1). A GWP is calculated over a specific time interval and this time interval must be stated whenever a GWP is quoted or else the value is meaningless.

Refrigerant ASHRAE Number IUPAC Chemical Name Net GWP per 100 years
R744 Carbon Dioxide 1
R12 Dichlorodifluoromethane 10,900
R22 Chlorodifluoromethane 1,810
R134a 1,1,1,2-Tetrafluoromethane 1 ,430
R410a R32/R125 (50/50) 2,087.5
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