Using tankless water heaters in cold climates
Natural gas tankless systems work best under cool conditions. (Photo courtesy of Lilly Funcion)
Dear Angie: Is it true tankless water heaters do not work well in cold climates? The water temperature in Anchorage, Ala. is in the mid-to-high 30s. I have had several heating companies come out to collect info to build proposals to replace my boiler and hot water heater. The first three specifically didn't recommend on-demand water heaters due to the cold temperatures of our city water. The fourth company went against the grain and will be proposing an all-in-one on-demand unit for home heating and drinking water. I didn't ask him his thoughts on the others' point of view, but have been looking for an answer. What are your thoughts? – Vinny B., Anchorage, Ala.
Dear Vinny: First, I commend you for taking the time to do your research and seek out multiple service companies for advice. You’ll almost assuredly be better off because of the time you spent doing your homework on the front end. To answer your question, many tankless water heaters can work in cold weather climates, depending on the type of tankless water heater it is.
As you likely know, tankless water heaters are able to provide an almost endless stream of hot water while occupying a very small space compared to a traditional tank unit, which requires the use of fuel to maintain a hot temperature. Plus, they heat only the water you use, so you waste less energy.
Though it is true that most electric tankless heaters do not perform well in cold weather, many natural gas tankless systems do. Many manufacturers build the gas tankless units to provide freeze protection to accommodate sub-zero temperatures.
A professional with experience with tankless water heaters can address the size of the system you need to accommodate your usage to ensure the unit provides enough hot water for you and your family to be comfortable. In a cold-weather area like Alaska, it’s important that the person doing the installation insulates the pipes feeding the unit. You also need to consider power failures. Even gas tankless heaters require electrical power to work, so if you experience a lot of power outages, tankless heaters might not be the best fit for you – unless you enjoy taking cold showers. Tankless units also require proper venting and should be installed close to gas lines to operate at their highest efficiency. Most homes can be retrofitted with a tankless heater, though some homes will require modifications to accommodate a venting flue. Larger homes also sometimes need more than one unit.
Because there are so many nuances involved with the installation and use, it’s important that only a qualified, licensed plumber install tankless water heaters.
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