What are waste water heat recovery shower pipes?

Heat recovery shower pipes are systems that collect the heat from the waste water that runs from the shower to the drains. They transfer the heat from the waste water to the cold water feed that comes back into the shower; it’s a method of heat recovery as, rather than throwing heat away, you are recovering the heat so you can use it back in the shower, saving energy, money and co2.

How do waste water heat recovery shower pipes work?

People often think that when water runs down a pipe it falls down the middle of the pipe but actually, it clings to the side of the pipe. A heat recovery shower pipe has a cold water pipe that spirals up around the main waste water pipe so when the hot water that you have just showered in runs down through plug hole and down the down pipe, it transfers the heat through the copper pipe to the cold water pipe wrapped around it. Heat recovery shower pipes are made of copper due to its thermal conductivity, which allows a quick transfer of heat.

save 67% of your hot water usage 

67% of the heat from the shower waste is transferred into the cold water heading to the shower with the Recoup systems when they are operating at their optimum level – this has been measured by the British research establishment.

The way a shower works is that when you get into the shower and set the thermostat, you have two pipes which come up to the shower, the hot pipe and the cold pipe. When you set the thermostat to the temperature you want to shower at, it mixes the hot and cold water together. So if the cold water heading to the shower gets hotter, then the shower needs less hot water to get it to the right temperature; this is why a heat recovery waste pipe works so well.

How can you incorporate them into your home?

Heat recovery shower pipes are more difficult to incorporate into an existing property because you have to try and combine the position of the waste pipe that coming from upstairs with the position of the incoming mains cold water feed that will be coming back up to the shower. This is very easy to do in a new build because you can make sure both the pipes are in the same place.

You can however get heat recovery shower trays which are easier to put into an existing property; they work in the same way but instead of the heat transfer happening in the pipe, it happens within the bottom of the tray.