Drain water heat recovery systems
Up to 20 per cent of home energy consumption comes from water heating, which is the second highest energy consumer in the house next to space heating.
Drain water heat recovery systems are an energy efficient technology that can reduce your water heater’s energy consumption by up to 25 per cent.
Drain Water Heat Recovery Systems
Learn how a drain water heat recovery system works and how it helps you save on your energy bill.
How it works
Technical cross section drawing of a drain water heat recovery system.
View PDF (332 KB).
Drain water heat recovery systems capture lost heat from hot water going down the drain and uses it to pre-heat cold water entering your water heater, as illustrated in the diagram to the right. The result is less energy is needed to heat water to the desired temperature. Energy is saved when you are using hot water at the same time it is flowing down the drain, during a shower for example. This is known as simultaneous flow consumption.
A typical drain water heat recovery system can reduce your water heater’s energy consumption by up to 25 per cent. Less energy consumption means lower energy bills for you.
Extend the life of your water heater
Since the cold water entering your water heater is pre-heated by the drain water heat recovery system, the water heater does not have to work as hard to heat the water so your water heater may last longer.
A drain water heat recovery system is compatible with any type of water heating system and as technology changes over time, your drain water heat recovery will reduce the energy consumption of any future water heating system you choose for your home.
Simplicity and reliability
A drain water heat recovery system is made of copper, has no moving parts, and requires no regular maintenance. The system has a product life of well over 30 years. Once it is installed, you can simply forget about it and enjoy the reduced energy consumption and utility bill savings it provides.
Is it right for my home?
Drain water heat recovery systems are recommended for homes with basements that have higher than average hot water consumption, usually consisting of 3 or more people. If your household’s primary method of washing is taking a bath over a shower, the technology may not be right for you. The greatest energy savings can be achieved if all the occupants in the house take showers.
Drain water heat recovery systems have an extremely long product life, 30 plus years, so it may still be beneficial to install the technology right now if there will be more occupants showering in the future.
If you are building a new home, installing a drain water heat recovery system during the building process, rather than after the fact, just makes good sense as you will be saving energy the minute you move in.
We recommend a licensed plumber install the drain water heat recovery system in your home. In most basic installations, it should only take a plumber a couple of hours to install the system. Drain water heat recovery systems can be purchased through your local plumber, at a plumbing wholesaler, or online.
To ensure you are purchasing and installing a system of the highest standard, Manitoba Hydro recommends that you select a system that is certified by the Canadian Standards Association (CSA) to B55.1 and B55.2.
For a non-exhaustive list of CSA B55.1 and B55.2 certified drain water heat recovery systems visit Natural Resources Canada’s website.