AquaSustain – DHP

OSO ‘s AquaSustain – DHP (Domestic hotwater HeatPump) is an environmentally friendly, efficient hot water cylinder with an integrated Heat pump, for the production of domestic hot water.

AquaSustain – DHP  contains a stainless steel hot water cylinder in the lower section with a heatpump in the upper section.

AquaSustain is highly efficient and delivers up to 3.5 times as much heating energy in hotwater as it uses in electrical energy. This is called the Coefficient of Performance (CoP). By contrast, the CoP of a standard electric device is 1, and the CoP of a gas boiler is less than 1.

AquaSustain uses R290 as a refrigerant, with a low Global Warming Potential (GWP) of 3 and an Ozone Depletion Potential of 0. It can heat water using the heat pump alone to 60°C.

AquaSustain draws air from outside, extracts thermal energy from the air and concentrates it in a higher temperature to heat water for showers and baths etc. Cold air is then discharged outside the property as more warm air is drawn in to continue the process.

The hot water cylinder is fully insulated to retain the heat.
The product is sized for the property to ensure sufficient supply of hot water for typical use. DHP products heat the water slowly over several hours to ensure that enough hot water is available. Do not switch the OSO AquaSustain off unless the property will be empty for more than 24 hours. Please note that the heating time from cold for the hot water cylinder is up to 8 hours and the product is designed to trickle heat the product over and extended period.

AquaSustain manages its temperature automatically and will switch off when fully heated.
It requires no regular attention from the householder.



Single footprint
R290 refrigerant
Stainless steel construction with 5 year warranty



Weight 150 kg
Dimensions 3.5 cm
Product no.OSO--
Product nameAquaSustain - DHP 200AquaSustain - DHP 260
Diameter — ⌀mm584584
Height - Hmm15401907
Weight emptykg--
Technical/ErP information
Capacity 40CLN/AN/A
Thermostat set pointC6060
Heat loss-EN 12897watt
Heat loss / 24 hrs - EN 12897kWh/day
AEC (energy consumption)kW/year8301255
Energy efficiency%133142
Tapping profile3XS–XXLLXL
Energy ratingA+–FA+A+
Primary Heating PowerkW
Primary coil sizeMins
Immersion Heating Power15001500
Heat-up time ΔT 55°C CoilMins
Heat-up time ΔT 55°C upper elementMins
Heat-up time ΔT 55°C lower elementMin
Recovery time ΔT 55°C coil 70%Mins
Recovery time ΔT 55°C upper element 70Mins
Recovery time ΔT 55°C lower element 70%Mins


OSO Hotwater product brochure UK
Manual  AquaSustain – DHP

Technical data Sheet Aquasustain – DHP

Information sheet Aquasustain – DHP