How many tankless water heaters do I need for my home?

In most cases, you need only 1 tankless heater for an entire house. However, if you really have a big house (2+ bathrooms), even the big 11 GPM Rinnai gas tankless water heater will not be enough to satisfy all your simultaneous hot water needs. The big tankless heater takes care of the most hot water needs.
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How many tankless water heaters Does my house need?

For larger households that typically use more than 85 gallons per day, two tankless systems, or the largest available model, are likely needed. For smaller households that use under 40 gallons per day, one unit should suffice.
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Do you need more than one tankless hot water heater?

The more hot water your household consumes per day, the more tankless water heaters you will need. Most tankless water heaters will produce 5 to 9 gallons of hot water per minute. You'll need two tankless water heaters if: If your household typically exceeds 9 gallons of hot water usage per minute.
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Why would you need 2 tankless water heaters?

It is possible to connect two tankless heaters to run parallel to each other, providing a larger amount of hot water on-demand. You could also get a larger tankless unit that can provide a higher flow rate.
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Can a house have two tankless water heaters?

Installing two small tankless water heater units is typically more expensive than installing one large one, but it can ensure clients have hot water on demand for a variety of simultaneous uses.
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Tankless Water Heaters: Which One Is Right For You?



Are two water heaters better than one?

Having two heating elements that run independently, dual-element water heaters are typically more energy-efficient than their single-element counterparts. Using less electricity can help lower your monthly energy bills and be better for the environment.
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What is the downside of a tankless water heater?

The main disadvantage of tankless water heaters is their upfront cost (unit and installation) is significantly higher than tank-style heaters. Including installation, tankless water heaters cost 3 times more than tank-style water heaters on average.
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How do I know what size tankless water heater I need?

How to Select the Right Size Tankless Water Heater
  1. Determine the maximum number of devices you want to run and their total flow rate. Then, add up their flow rates (gallons per minute). ...
  2. Determine required temperature rise. ...
  3. Sizing Example: An average shower will be between 104–106° and uses 2.6 gallons of water.
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How many people can use a tankless water heater?

A basic size requirement for choosing between them is that for one or two people, a tankless electric heater may be adequate. For more than two people, a gas fired tankless heater is the way to go.
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Can I run tankless water heaters in series?

Tankless electric water heaters can be installed in series.
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Can a tankless water heater run a whole house?

Electric tankless water heaters can be installed in any location within your home with the appropriate hookups. Their compact size frees up valuable space within your home. For gas tankless water heaters you will need to utilize specific venting, which will impact where you can install throughout your home.
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Is one tankless water heater enough?

In most cases, you need only 1 tankless heater for an entire house. However, if you really have a big house (2+ bathrooms), even the big 11 GPM Rinnai gas tankless water heater will not be enough to satisfy all your simultaneous hot water needs. The big tankless heater takes care of the most hot water needs.
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Are tankless water heaters worth the money?

According to the U.S. Dept. of Energy, a tankless water heater is more efficient and uses less energy than a conventional water heater, providing a $25 to $107 in annual savings. If your hot water use is low (less than 41 gallons per day), a tankless water heater will be 24% to 34% more efficient.
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How big of a water heater do I need for a family of 4?

Water Heater Sizes

The answer to this question will vary depending on the total number of kids you have. For example, a family of 3 to 4 people should purchase a 50 – 60 gallon water heater. On the other hand, a household with 5 – 7 people may require a water heater with a 60 – 80 gallon water tank.
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Why does my house have two hot water heaters?

In series, the water comes in to the first water heater, then passes through the second hot water heater, and finally goes to your fixtures. If you turn off the second water heater, then the water in the second one cools down between uses. This results in very long warmup times.
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How long do tankless water heaters last?

Some people hesitate to decide on a tankless water heater because they can be a slightly higher cost; however, you get significantly more life out of one. A standard water heater tank lasts about 8-12 years. A tankless water heater can last as long as 25 years!
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Is a tankless water heater good for a large family?

From a comfort standpoint, a tankless model can ensure hot showers for the whole family, enough warm water for dishes and laundry and a restful soak in a warm bath after a long day at work.
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How many gpm should a 2 bathroom house have?

SELECTING A TANKLESS WATER HEATER

Consider how many of these needs you may have simultaneously to determine the maximum flow rate you require. For a home with 1 bathroom, we recommend 6-7 GPM; 2 bathrooms, 8 – 9 GPM; and 3+ bathrooms, 9-11 GPM.
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Why is tankless water heater installation so expensive?

Tankless water heaters have a higher initial price compared to tank heaters, costing homeowners between $1,200–$3,500. The higher cost is a result of a more labor-intensive set-up, as new gas and water lines are required for installation. For electrical tankless heaters, new electric wiring will need to be installed.
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How many GPM is 2 showers?

It is recommended that you use 1.0 GPM for bathroom water needs. If you are running two different showers at the same time, you will need at least 5 gallons of water from your tankless water heater. If you need to run both your washing machine and shower at the same time, you will use around 4.5 gallons per minute.
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How many gpm do you need for a house?

For most single-family homes, a minimum flow of 6 GPM is suggested from a well or spring. This flow would provide 360 gallons of water each hour, which would be sufficient to meet most home water peak demands.
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How big of a gas line do I need for a tankless water heater?

A typical tankless water heater will need a ¾-inch gas line. However, if there is sufficient pressure and the run length is short enough, a ½-inch line may be sufficient with certain tankless water heaters, such as the Noritz EZ Series.
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Are tankless water heaters worth it 2021?

Energy Efficient

The U.S. Department of Energy reports a tankless water heater is 24% to 34% more energy-efficient than storage tank water heaters—as long as you use around 41 gallons per day. However, even if you double that amount, they are still 8% to 14% more efficient.
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Do tankless water heaters freeze up?

While it's hard to imagine, a tankless water heater can freeze even if it's installed inside your home. Here's what you can do to fix the problem. You'll need to repair this situation quickly as freezing can cause damage and affect your running water and drainage.
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Can a tankless water heater flood a house?

But because tankless water heaters don't actually store water at all, the risk of flooding is tremendously reduced (although damaged pipes still pose a potential risk).
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