• The Farmyard Offices, Mountain Honey Estate, 74 Sterkfontein avenue, Doornkloof, Pretoria, Gauteng, South Africa
  • enquiries@oneenergy.co.za
  • 0861 4328 464 or 0861 HEATING


Residential Heat Pumps | Water Heating SYSTEMS


Very basically a heat pump REPLACES your element in your geyser.
A geyser element uses 3 or 4 kW of electricity per hour and a heat pump uses 1.1 kW or less per hour. So the heat pump will save you at least two thirds (67%) of your water heating costs annually.

How does it do this?

A heat pump uses a reverse refrigeration cycle to draw energy out of the ambient air, saving you a lot of money.

The 5 main components of a heat pump are:

  • A fan
  • An evaporator filled with refrigerant gas
  • A compressor
  • A heat exchanger
  • An expansion valve.

The Heat Pump Process:

  1. The fan draws warm ambient air into the heat pump across the evaporator transferring energy to the ice cold refrigerant up to room temperature.
  2. The compressor then “pumps” the gas heating it up to about 160 degrees – (think of how a bicycle pump gets hot when you compress the air in it)
  3. The hot gas is passed through a tube in one direction and cold water from your geyser flows in the opposite direction so that transfer of hot energy to cold water occurs – this warms up the water.
  4. The cooler gas is finally passed through an expansion valve so that it cools below freezing. (Think of the cooling effect when you blow through a straw)
  5. The whole cycle then repeats itself.
    In this manner our 5 kW output heat pump produces 120l of hot water per hour (when ambient temperature is above 20 degrees C and heats the water from 15 – 55 degrees) – A heat pump does work in cold weather – as low as -4 degrees.


How a Heat Pump is connected to your existing geyser

How a Heat Pump is connected to your property


What are the Advantages of Heat Pumps over Solar Collectors?

The main advantages of a heat pump are the ability to re-heat a geyser a few times per day and that it can work day and night, rain or shine. A solar system will only save you more money if its capacity exceeded its demand which is highly dependent on the usage pattern.

The Eskom rebate of between R3668 and R4320 depending on geyser size, is taken directly off your quote no waiting for repayments, where Solar you will have to wait up to 8 weeks for your repayment.

How long does a Heat Pump take to heat water?

An 4.7kW heat pump will heat the water slightly faster than a 4kW electrical element typically found in 200L geysers. The heat pump produces 4.7kW of thermal energy under specified conditions while using as little as 1.2kW to do so.


Does a Heat Pump Need Maintenance?

Our heat pumps range requires virtually no maintenance of the system except for making sure the evaporator is clean from dirt and leaves. We do however recommend that the system be checked annually to ensure that you are getting the best possible efficiency out of the system. We have a monthly eminence plan called Heat Sure which also extends our product warranty to 5 years. Our Heat Pumps should last for up to 10 years.


How much can I save?

A typical family of 4 that uses water very conservately uses about R500 of electricity per month to heat water. Installing a heat pump will guarantee you a instant saving of about R350 per month which means the machine will pay for itself in less than 3 years.