Best Water Heaters For Constant Hot Water

Gary Johnson
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Some of us can’t do without a nice warm bath or shower before bed.

Why is that an issue?

Well, if you are forced to wait for the hot water to come through while you wash your hands or brush your teeth, those are not wasted minutes.

They add up and take away from quality time you could spend with your family and you are just being grumpy waiting for the water to warm up.

Adding one of the best water heaters for high volume water heaters can help with a number of water issues when you run into the next one you need solved let’s learn how to upgrade to a tankless water heater.

Stiebel Eltron Tankless Water HeaterBest OverallStiebel Eltron Tankless Water Heater
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1. Stiebel Eltron Tankless Water Heater

Our rating: 9 / 10

Stiebel Eltron Tankless Water Heater

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  • Great warranty
  • Easy to install
  • Can heat water instantly
  • No storage tank needed


  • Expensive
  • Must be installed near the source of water

Thanks to its advanced thermo-sensor, this tankless water heater from Stiebel Eltron can instantly go from standby to peak performance when it detects a sudden demand for hot water.

Main Features:

・Energy efficient: Uses only what you need, when you need it

2. Rinnai RUC98iN Ultra Series Indoor Natural Gas Tankless Water Heater

Our rating: 8 / 10

Rinnai RUC98iN Ultra Series Indoor Natural Gas Tankless Water Heater

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  • Cost efficient
  • Reliable
  • Durable
  • Easy to install
  • Solid customer support

When it comes to water heaters for constant hot water, the one I prefer is this Rinnai RUC98iN Water Heater. It’s not too expensive for the features it offers, and it’s also solid enough to last a long time.

This water heater is capable of heating water for two faucets or showers. It’s also compact enough to fit almost anywhere, and it’s easy to install too.

I’m also captivated by the thoughtful design. The controls are simple to use, and they’re also sensibly placed. The digital display is easy to read, and it’s also responsive.

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Our rating: 7 / 10

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  • Includes backup options for cloudy days
  • Easy DIY installation
  • 60 gallon capacity
  • Compact design
  • Warranty: lifetime homeowner warranty
  • 15 years warranty for solar panels
  • Energy and money savings
  • Made in USA


  • System is designed for small home water usage
  • Long delivery times
  • Assembly can take a lot of time – up to 8 hours
  • No way to add timer for shut-off
  • Some leaks noted by users after 1 – 2 years

The idea behind these water heaters is simple. They use the sun¡¦s heating power to heat water quickly. They store the water until it is needed, and this eliminates the need to warm the water first, saving on costs and energy used. In cooler climates, the solar water heaters will keep water at an optimal temperature for longer periods of time.

This is not the best option if you live in an area with a mild climate. However, for locations that have cold winters, this system can really make a difference on your monthly water bill. With a good system, you can enjoy a shower on a cold morning.

4. Eccotemp L10 2.6 GPM Portable Tankless Water Heater

Our rating: 5 / 10

Eccotemp L10 2.6 GPM Portable Tankless Water Heater

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  • Hot water on demand
  • Energy efficient
  • Portable and easy to install


  • Price point can be a bit high
  • Limited control over flow of water flow

You’ve likely heard of tankless water heaters, but did you know there’s also a choice for tankless water heaters? Its great for providing hot water at high temperatures like what you’d find in a shower or a bidet.

While our top pick does cost a few hundred bucks, it’s well worth it for the convenience of having constant hot water for fast showers.

If you’re looking for a smaller alternative, the Eccotemp L10 is small enough to be portable, which means you never have to worry about lugging around a large tank. You also have the option of installing it on the ground or on the wall; it’s your choice! This little water heater is a natural in places like sun rooms, bathroom additions, and small bathrooms.

Frequently Asked Questions (FAQ)

What brand of water heater is the most reliable?

In our experience, the most reliable brand of water heaters are American standard. While we haven’t tested every model of water heater available, American standard has consistently performed the best for us every time. They may not be the most expensive models you'll find at your local hardware store, but we'd recommend them over any of the lower quality brands like Rheem, AO Smith, Bradford White, or Niagara systems.

Why are we telling you this?

Because if we could build our own small-water-heater rankings, we'd put American Standard at the top of the list based on our experiences. If you’re looking for a discount water heater, we'd wager that using an American Standard model will take you much further than one of the brands we wouldn't recommend.

What is the most efficient water heating system?

While having a constant flow of hot water is preferred, efficiency is important as well. High efficiency water heaters will use less energy to generate the same amount of hot water.

High efficiency means sacrificing more for being a little less convenient however. Some solar water heaters, like the Zimsen, require users to attach collector panels to their roofs and collect the sun’s rays, then transfer that heat to the water. In the case of the Zimsen, this takes time so hot water is not always available immediately. In comparison, electric water heaters offer instant hot water but are not as efficient.

The best possible water heater for you should be a highly efficient one that also offers instantaneous hot water. This generally means an electric tank-less type.

Is it better to have hot water on constant?

In a word, Yes! Many people often forget about the importance of continually having hot water in their homes. Having an electric water heater that maintains a minimum temperature of at least 120 degrees F is important as it allows for a steady flow of hot water that is easily accessible to your family. This means no more waiting for the water to warm up in order to have a hot shower, therefore eliminating the need to turn on the water in the shower before hand to warm it.

It is important to maintain the temperature of water in your home within a certain temperature range. If you like very hot water for example, you can train yourself to take showers at hotter times of the day when electricity rates are lower (usually in the middle of the day). If hot water is not available at all times, then you'll be more likely to take shorter or cooler showers.

What causes a water heater to run out of hot water?

When your water heater runs out of hot water, it usually means you've overused the hot water. Think about it: you've had running hot water for your showers, baths, dishes, and laundry. After all those uses, you've used up all the hot water naturally.

The trick to keeping your hot water tank from running out is to have an ample water heater capacity in your home or apartment. This isn't just about the highest BTU rating either.

With modern tank design, lots of BTU doesn't necessarily mean lots of hot water. Water tanks are typically sized to allow a certain amount of hot water as well as a certain amount of cold water. These settings are determined by municipal water heat based on the expected usage and climate.


You want hot water to be available as soon as you turn on the shower, don’t you? Of course, you want it to be ready fast! But how do you do that? Do you have to spend a fortune on buying a new water heater? Is it even an option? To answer these questions, we’ve researched the current market to find out the best water heater for constant hot water modes. In this article, we will look into the water heater market, and help you understand how to get constant hot water without breaking the bank.

Our Recommendation

Stiebel Eltron Tankless Water HeaterBest OverallStiebel Eltron Tankless Water Heater
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