Why do we use CO2 to heat water?

There are a number of quite technical reasons why we use CO2 (carbon dioxide) instead of other refrigerants in the Reclaim CO2 heat pump.  Fundamentally it comes to two things: first, we want the best performance from the refrigerant, no matter how cold the weather.  Second, we want to minimise the system’s environmental impact, for the whole it’s life.

CO2 is one of the highest efficiency refrigerants available for water heating.

CO2 operates at a really wide range of temperatures.  This means however cold the air is outside there will still be plenty of hot water being produced using a minimal amount of energy.  For example, at a chilly 1°C a Reclaim CO2 heat pump will have a COP of 4.2, delivering more than four times as much energy out as electricity in!

A completely natural gas with very low global warming potential.

The other main benefit of CO2 as a refrigerant is that it is a completely natural gas and has a very low Global Warming Potential (GWP).  In fact, it is the baseline gas on which all other gases are compared for how much they contribute to the climate crisis if/when they are released to the atmosphere.  If 1kg of CO2 refrigerant leaks then it has 1kg of Global Warming Potential.  Compare this to the most widely used hot water heat pump refrigerant R134a which has a GWP of 1,300.  If 1kg of R134a is leaked it is the equivalent of 1,300kg (1.3 tonnes) of CO2 in Global Warming Potential.

We use CO2 to protect your pocket and to protect the environment. Find out more about the Reclaim CO2 Hot Water Heater.