Updated December 21, 2017 by Tina Morna Freitas

The 10 Best Tankless Water Heaters

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Best High-End
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This wiki has been updated 22 times since it was first published in March of 2015. If you've ever had the unpleasant experience of the spray suddenly going cold on you in the shower, or wondered why most homes heat water constantly when it is only used occasionally, then it's time to consider a tankless water heater. Our selections include a variety of units that will not only save you money, but also provide an endless supply of comfortable H2O for your whole family. When users buy our independently chosen editorial selections, we may earn commissions to help fund the Wiki. Skip to the best tankless water heater on Amazon.

10. SioGreen IR288

9. Rheem RTEX-13

8. Eccotemp FVI

7. Takagi T-KJR2

6. Rheem RTG-84

5. Rinnai Ultra Series

4. EcoSmart Eco 27

3. Takagi T-H3

2. Camplux 5L Portable

1. Stiebel Eltron Tempra

A Tankless Job Is A Job Worth Doing

That's something called standby heat loss, and it's a gouging sword in the guts of your gas bill.

Fans of the hit television series Breaking Bad (and I promise no spoilers here) may remember an episode in which Walt, the main character, uses his illegally acquired money to make much needed repairs on his house. The repairs become a kind of metaphor for his desperate attempts to fix his relationships with his wife and son, and, as a result, they become an obsession.

During one of several trips to the home improvement store, a sales clerk asks him about the water heaters at which he's looking. Walt inquires about tankless models, and the clerk, presumably working on commission, lights right up.

That moment is based on the very real fact that tankless water heaters are more expensive than their enormous counterparts, but if you're willing and able to take the plunge, they'll save you a lot more money in the long run.

For starters, tankless heaters don't store a big tank full of water–hence the moniker tankless.

Traditional tank heaters have to keep that large body of water at a constant temperature so that a certain amount of hot water is available at all times. If you use up that tank of hot water, you have to wait for the new water coming into the tank to heat up.

That means you're spending more time and gas keeping many gallons of water hot even when you might not be using them. That's something called standby heat loss, and it's a gouging sword in the guts of your gas bill.

Tankless heaters, by contrast, circulate a flow of incoming water past a heat exchanger and back out the unit, heated and ready to go. There's no residual energy loss, and there's an endless supply of hot water. Gas models require additional ventilation, which is expensive to set up, and electric models will certainly raise your electric bill, but the savings will undeniably be present, and the average tankless heater will outlive a traditional heater by five to ten years.

No Tank Doesn't Mean No Options

At first glance, going tankless might seem like a simple change. After all, the only difference is that you're nixing the tank in favor of the much smaller heat exchanger. Well, it turns out there are some important differences to consider among tankless water heaters that could make or break your purchase and installation.

If that's the case, it's going to be much less of a hassle to go electric.

Tankless water heaters come in two main categories: gas and electric. Electric models use an electrically powered heat exchanger, which is a hefty tax on your power bills, but nothing compared to the cost of standby heat loss.

Gas powered tankless heaters come divided into two subcategories. There are your standard models, which require a basic ventilation system, and then there are condensing models which double the number of heat exchangers. That's great if you only have the one tankless unit to supply a whole house with hot water, but they require additional ventilation construction, as well as a condensate drain to evacuate the unit of moisture.

You're going to need to take a look at the available gas lines coming into your property before choosing a gas powered tankless water heater, as they may require a larger intake pipe than you currently have. If that's the case, it's going to be much less of a hassle to go electric. For the time being, electric will be more expensive, but natural gas costs are projected to surpass electricity costs in the coming years.

America Is Slow To Go Tankless

Say what you want about the US; there's a lot of space here. Sure, some of our cities are ridiculously overpopulated and many of our rural ares are equally underpopulated, but when you average it all out, there's a lot of room to breathe.

The best part is that units in the US are priced to appear as a luxury item.

That's why a lot of American things are simply bigger than they are elsewhere in the world. Streets and the cars that drive on them, buildings and their work forces, houses and their families–all on the large side compared with the majority of the developed world.

It's no surprise, then, that even though we had our hands on tankless water heating technology in the late 1800s, we opted to standardize large tank water heaters in homes throughout the land. We had the space for it, so why bother economizing?

Now that gas and electricity are becoming so expensive, a lot of homeowners in the US are finding different ways to save on their energy costs, one of which are these tankless heaters. They've been immensely popular in Europe and the East for ages, so it was only a matter of time before our economic reality and their convenience merged.

The best part is that units in the US are priced to appear as a luxury item. People view tankless water heaters as a status symbol, a marker of the savvy and wealthy homeowner. As demand increases, unit prices are sure to come down, but now's the time to get in on the trend. It's never to soon to start saving.

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Tina Morna Freitas
Last updated on December 21, 2017 by Tina Morna Freitas

Tina Morna Freitas is a writer who lives in Chicago with her family and three cats. She has a B.A. in anthropology with a minor in English, and has built a freelance career over the years in writing and digital marketing. Her passions for cooking, decorating and home improvement contribute to her extensive knowledge of all things kitchen and home goods. In addition, her 20 years as a parent inform her expertise in the endless stream of toys and equipment that inevitably takes over the homes of most parents. She also enjoys gardening, making and sipping margaritas, and aspires to be a crazy cat lady once all the children are grown.

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