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Hot Water Heater Sizes: Which One is Right for You?

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Your water heater is an amazing appliance. It delivers clean, hot water to your shower and helps you wash your clothes and dishes safely and easily. But a water heater can feel less like a wonder and more like an annoyance when you’re constantly running out of hot water. How do you prevent that? Having the correct size of water heater for your household is the key.

Tankless vs. Traditional Water Heaters

Your first decision is whether to install a traditional storage tank water heater or a tankless water heater . While tank heaters are still the most common, tankless heaters are growing in popularity.

What’s the difference?  Tank water heaters have a storage tank that constantly heats water for household usage. The pre-heated water flows to the point of use as needed. The storage tank refills, and new water is heated.

Most of these water heaters hold between 30 and 60 gallons. They’re a reasonably priced choice for many households, especially those with steady demands for hot water.

Tankless systems heat water almost instantly, on demand. Instead of being stored, water passes through heating coils before delivery to each point of use. Tankless water heaters are more expensive than tank models, but they offer savings on energy use. They’re also more compact and can be installed in a small area.

Determining Your Ideal Water Heater Size

Once you’ve chosen a water heater type, determining the ideal size is the next step.

Storage Tank Heaters

You need to know the tank’s First Hour Rating (FHR). This rating tells you how many gallons of water the heater can produce in a one-hour period.

You also need to calculate your peak hour demand. That is the amount of hot water your household uses during a high-demand hour. Add up the demand, in gallons, of all the points of use that you would employ in a busy hour. Each activity has an average number of gallons used.

Once you know those two numbers, you can select a water heater that meets your needs. Typically, larger tanks cost more—so you really want to get the math right.

Tankless Heaters

For a tankless heater, you need to determine the flow rate (gallons per minute) that will satisfy your household’s demand for hot water. The calculation requires figuring out how much hot water you’ll be using simultaneously, based on the flow rate of different points of use. You also need to know the groundwater temperature in your area. These numbers will lead you to tankless water heater models that would work well for your household.

Let the Experts Help You!

The process of calculating water heater size and choosing a model can be quite complicated, and that’s where Climate Experts Heating & Cooling can help. Call us to set up a consultation with one of our professionals. We will work through all of the steps, do all of the math, and then recommend water heater models that would work for you. Our experts can offer advice about long-term planning and make sure that you have sufficient space to install each model.

Incorrect calculations mean that you will run out of hot water during peak times or pay for a hot water heater that’s more than you need. Why not ensure a great outcome by giving us a call? Contact us for more information and a free estimate today!

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