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April 01, 2023

Pond Heating Duratech Plus Heat Pumps Duratech Dura 10 Plus Heat Pump

Duratech Dura 10 Plus Heat Pump

Duratech Dura 10 Plus Heat Pump

Duratech 10 Plus Heat Pump

With the rapid increase in energy costs year to year, one of the most expensive aspects in fishkeeping is in heating the pond. With the Duratech Dura 7 Plus heat pumps this can be achieved in the most efficent cost effective way possible

Heat pumps have been around for many years and were primarily used for commercial and domestic pool and spa heating. Their use was fairly restricted in other areas as the water heating stopped when air temperatures dipped below 7°C.

To the Koi Keeper, Heat Pumps represent the most efficient and cheapest way to heat a koi pond. Although heating can be used to promote koi growth, the most important part of pond heating is to stabilise the temperature during seasonal changes and to provide protection to your fish during the winter. Now, with the introduction of new refrigerants and modern control technology, the DURA+ range from DURATECH® offer a highly efficient heat pumps will keep working with outside air temperatures down to -10°C.

Key Features

  • Can operate down to -10°C
  • High efficiency (COP of up to 6)
  • Oversized heat exchanger for improved efficiency
  • Can heat or cool water
  • Durable & corrosion resistant with its plastic/ stainless steel casing
  • Automatic hot gas defrost function
  • Titanium heat exchanger will not be damaged by salt and other pond additives
  • Automated electronic control
  • Quiet in operation
  • Easy to install
  • Extremely efficient and reliable

How does it work?

DURATECH® heat pumps utilize the sun’s free heat by collecting and absorbing energy from the outside air. This energy is then transferred to the pond water. Your existing pond pump circulates the water through the heater and warms the pond. The unit contains a fan that draws in outside air and directs it over the surface of the EVAPORATOR (energy collector). The liquid refrigerant within the EVAPORATOR coil absorbs the heat from the outside air and the refrigerant becomes a gas. The warm gas passes through the compressor where it is compressed to form a very hot gas, which then passes through the CONDENSOR (water heat exchanger). It is here that the heat exchange occurs as the hot gas gives up the heat to the cooler pond water circulating through the coil. The pond water becomes warmer and the hot gas is cooling down as it flows through the CONDENSOR coil, returns to its liquid form and, after passing through the expansion valve, the whole process begins again.

Duratech Heat Pump Schematic

Highly Efficient

The energy is collected from the air outside and transferred to the pond water. For each kW consumed by the DURA+ heat pump, 3 to 6 kW are returned to the pond.

The Coefficient of Performance (COP) is the measurement of the efficiency of the unit. A COP of 3 means that for every 1KW of electricity you use, you will transfer 3KW of heating to the pond water. As this unit collects its energy from the air, the lower the air temperature, the less efficient the unit becomes and the lower the COP will be. However, even at an air temperature of -5°C., the COP is just over 3 when heating the pond water to 5°C. The COP for the refrigerant used in the DURA+ range of heat pumps is shown below.


The DURA+ heat pumps must be installed outside. It will heat the pond all year around and will even work efficiently with outside temperatures as low as -10°C. In addition, the DURA+ heat pumps also a cooling mode. This could be a useful feature if ‘heat ramping’ is required, during the quarantine procedure.
Environmental Friendly

DURA+ heat pumps are less harmful to the environment because 80% of the energy produced is collected from the outside air and therefore purely natural. The refrigerant gas used, R410a, has no harmful effect on the ozone layer. The DURA+ heat pumps are very energy efficient and can even reach a COP value of 6.

Quality Construction

The Dura+ heat pump bodies are made from PVC and stainless steel and are strong and durable, making them suitable for a long life outdoors. The heat exchanger is made from titanium and is resistant to chlorine, salt and other chemicals usually used in ponds.
Easy Installation

The unit is intelligently designed and remarkably compact for easy installation. The heat pump is installed on a by-pass after the filtration pump. This allows it to be isolated during the warm summer months when it is not required. Alternatively, the heat pump can be fitted to a separate system with its own pond pump and flow & return network. The diagrammatic sketch shown below shows a typical pool layout. For Koi ponds, a UV clarifier is fitted on the return to the pond.

Advanced Control

The integrated microprocessor monitors all the sensors and controls the device without any intervention of the user. Electronic display and control with easy operation is standard. The integrated flow switch will sense the water flow and automatically start the heater when the pool pump starts and stops the heater
when the pump shuts off.

Duratech Dura 7 Plus Cost Comparison

As an good guide to the efficiency of these heat pumps, for every kw used by the heat pump approximately 4-6 kw of output energy is returned to the pond water in the form of heat. Conventional electirc heaters produce the same amount of energy for the size of the heater, for example a 1kw electric heater produces 1kw of output energy in the form of heat. So the Duratech Dra Plus heat pumps are approximately 4-6 time more efficient. See the example running cost comparison table below.

Duratech Cost Comparison Chart

Technical Data & Pond Capacity

To get best results from the Dura+ heat pumps, we recommend that a suitable winter pond cover is used.

UnitsDura 7+Dura 10+Dura 14+Dura 19+
Heating CapacityKw79.814.319.6
Heating OutputBtu2390033450485007500
Power InputKw1.21.712.463.44
Max Pond Volumem³/Gallon30/660040/880060/1320080/17600
Running Current 5.227.4310.7014.96
Maximum CurrentAmps6.59.3013.4018.70
Power SupplyV/Ph/Hz220-240/1/50220-240/1/50220-240/1/50220-240/1/50
Controller Electronic
Condensor Titanium Heat Exchange
Compressor Type RotaryRotaryRotaryRotary
Refrigerant R410aR410aR410aR410a
Air Flow High


Air Flow Lowm³/hour1800180020002700
Fan Quantity 1111
Fan Power Inputwatt120120120120
Fan Speedrpm850/750850/750850/750850/750
Fan Direction HorizontalHorizontalHorizontalHorizontal
Noise Leveldb(.A)50515154
Water Connectionmm50505050
Nominal Water Flowm³/hour3.
Max Pressure LosskPa10101010
Net Dimensionsl/b/h mm905/420/650905/420/650905/420/6501200/470/850
Shipping Dimensionsl/b/h mm1030/440/7001030/440/7001030/440/7001240/480/900
Net weight / Shipping weightKg55/6060/6577/82117/128

SKU Description Price Order
DURA10 Duratech Dura 10 Plus Heat Pump C a l l C a l l

More Duratech Plus Heat Pumps

Duratech Dura 7 Plus Heat Pump
Duratech Dura 7 Plus Heat Pump
Duratech Dura 14 Plus Heat Pump
Duratech Dura 14 Plus Heat Pump
Duratech Dura 19 Plus Heat Pump
Duratech Dura 19 Plus Heat Pump