Tankless water heaters offer an energy-efficient option for homeowners, and some new models can reduce home water- heating costs by up to 50 percent. Tankless heaters offer on-demand convenience, because these heaters don’t have a holding tank. Water is heated on an as-needed basis, not heated and stored for hours like a traditional tank. This reduces energy loss from sitting water and also guarantees a warm shower, even if you’re the last per- son in line. Plus, tankless heaters are powerful, yet compact. Most can be wall-mounted inside or out- side the home. Although sizes vary, the average tankless unit is about 24 inches high and 18 inch- es wide—significantly smaller than the traditional 40-gallon tank. Plus, with today’s tankless units you can dial in the water tempera- ture with a digital controller. Thanks to advancements in design and technology, some units even offer self-modulating “smart” technology. For example, the EcoSmart tankless water heaters from Rheem will adjust how much energy input is needed based on how much hot water is demanded. Both gas-fired and electrical water heaters are available in a wide range of sizes. Note that gas-fired tankless heaters require the exhaust and air-intake to be vented outside, separately from all
other appliances, which can com- plicate installation. Electric tankless heaters require no venting, but they do require sig- nificant available power supply. For example, the EHT staff recent- ly explored installing a new tank- less heater at one of our project houses. The home in question had a separate mother-in-law suite in the basement, which was operating one of two separate tank-style heaters to accommo- date the different dwellings. The downstairs suite seemed like a prime candidate for an EcoSmart Eco- 18 unit, sized for two bath- rooms for up to three people. However, after consulting with an electrician, we determined the tankless unit was not a good fit for the home. Why? Because, although the electric tankless units do conserve energy when the heating coils aren’t active, once they do activate, they draw a great deal of electrical power in short intervals. The Eco- 18 model required two 40-amp breakers for installation, and it had a 75-amp draw. According to the electrician we consulted, the house in question was already approaching maximum 200- amp electrical capacity before adding the new tankless unit. He explained that if the tankless unit were to kick on at the same time as another high-amp appli- ance, such as an air-conditioner, then the lights in the house would begin to flicker and the electrical supply would be too strained to power everything.
Is a Tankless Water Heater right for Your Home?
The Big Draw of Tankless
Electric Water Heaters