What's all the fuss about...? Tankless Water Heaters

There has been a lot of talk in the media about a huge variety of new, “green” technology – from “smart” electrical grids to solar panels, fuel made from algae to hydrogen-powered vehicles.  The ideas for creating a more sustainable infrastructure are countless, but do they really work?  Over the next few months, From the Green Seat will introduce you to some of these technologies, talk about the pros and cons, and try to help you unravel the mysteries around “green” technology.

This month, tankless water heaters will be our subject.  “Tankless?  How the heck do you get hot water without a tank?”  Through a computer chip, that’s how!  Tankless, or on-demand, water heaters work through a series of sensors and a small computer that sends a signal to the heat source (gas or electric) when the tap is turned on.  Water flowing through the heating element heats up within a few seconds, sending hot water quickly to the tap.

The biggest benefit of a tankless heater is energy savings.  With a regular hot water tank, energy is expended constantly to maintain the temperature of the water stored in the tank.  And a lot of that energy is lost through “standby loss” – heat that escapes through the walls of the tank as water sits unused.  The U.S. Department of Energy estimates savings of up to 30% on the cost of heating water for a small household using a tankless system – savings may be less for larger families.

Another way to use a tankless heater is at point-of-use.  In larger houses, you may be able to save even more by installing a tankless system on each floor, or in heavy-use rooms like the kitchen or master bath, to reduce the amount of water left in the pipes between the heater and the taps.

Additional savings can be found in the long life of tankless systems.  Regular heaters may last up to 10 years; tankless heaters can last at least 20.  They are easier to repair than regular hot water tanks as well.

One downside to a tankless system is demand.  If you have a large family or house, one system may not provide enough hot water for multiple use points – someone taking a shower might get a cold surprise if the kitchen sink is turned on!  Hoewever this is also sometimes an issue with regular water tanks as well, and can be mitigated by using more than one heater.

Another con is installation.  Replacing your tank system with a tankless heater is, unfortunately, not a do-it-yourself project.  It requires extensive knowledge in plumbing and electrical work, and is best handled by a professional.  They also can be expensive – prices range from $600-$1500 depending on output rates and size.

Consumer Reports has an evaluation tool available on their website to help you determine if a tankless system is advantageous, or if you would be better served by a high-efficiency tank.  Click here.