How Do I Know What Size Tankless Water Heater I Need?

How Do I Know What Size Tankless Water Heater I Need

The tankless water heater has been popular in Europe—as well as other parts of the world—for decades. However, most consumers in North America have only learned about the benefits of tankless water heaters within the past few years.

Tankless water heaters eliminate the need to constantly empty the tank because it provides a near-endless water supply—an ideal situation for many homeowners. This kind of heater focuses on flow rather than capacity, making it a better option for many American homeowners.

Here are some tips to figuring out what’s the best water heater size for your home. Are you planning to buy your own tankless water heater? If so, this post is for you.

1. Identify the groundwater temperature.

Generally speaking, less energy is needed to heat water if the water’s initial temperature is already pretty warm. For instance, it takes significantly more time (and energy) to boil cold water than it does to bring already hot water to the boiling point.

That being said, your groundwater temperature will dictate how big (or how small) your tankless water heater should be. Homes in the northern regions have colder groundwater (about 37 F) compared to those in the far southern regions (70 F and higher).

Therefore, a homeowner in the north would need more energy to heat their incoming water, which translates to a larger tank. On the other hand, a small or medium-sized heater would yield sufficient energy for a small family in the south.

2. Check the mounting space.

How Do I Know What Size Tankless Water Heater I Need1A tankless water heater is much smaller compared to units with a storage tank. This means they can be wall-mounted. Gas-fired units are typically 30 in. high and 20 in. wide. Electric units are even smaller, at about 10 in. in height and 7 in. wide.

If you’re planning to mount your water heater, you’ll need to take exact measurements of the walls and the room’s dimensions. Work with a professional to determine what water heater size is best given the available wall space you have.

3. Determine the flow rates of water.

How much hot water do you need in your household? Do you need to heat two showers at the same time or just one shower with a few sinks? The efficiency of your tankless water heater is determined by the rates of water flow inside your property.

A low-flow water head will probably require 1.5 gallons of hot water every minute, which is also referred to as GPM. A running bathtub might consume 4 GPM, while a faucet when someone is doing dishes may run 1.5 GPM. To know the flow rates, check the energy guide tag or the manufacturer’s model tag.

Your household’s water needs will dictate the size of the heater. A larger house with an above-average need for water will need a bigger tankless water heater than a smaller house with just one or two people in it.

Finding the best tankless water heater size is not that difficult as long as you’re guided by these tips. If you need help or more information about tankless water heaters, our team of friendly experts will be glad to assist. We look forward to hearing from you!

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