So you’ve finally decided to retire that old water heater. Maybe it doesn’t produce hot water anymore, or it has been breaking down too frequently, or it no longer meets the demands of your newly expanded family. Now, knowing when to replace a water heater is the easy part, but deciding the right water heater size for your home is not always straightforward. Below, we will show you how to size a water heater correctly.
Check the Water Heater’s First Hour Rating
The first step of sizing a storage water heater is to understand the first-hour rating. This figure signifies the gallons of heated water the unit can consistently dispense in an hour when the tank is full. The rating also indicates how well the heater will serve you during peak hours. Choose a water heater with a higher rating than the amount of water you use during the busiest hour. 
Know Your Peak Hour Demand
Usually, every home has a time frame where almost everyone wants to use some hot water. Mostly in the morning or evening. Now, if the average amount of hot water each person uses to shower is 10 gallons, and there are 3 people who shower around the same time, multiply 10 gallons by the 3 people.
That’s 30 gallons of hot water for showering alone during peak hours. Apart from the baths, take into account the heated water you’ll use to wash dishes, prepare food, shave, and doing laundry during that peak window. That means you’ll need a water heater capacity of around 40 to 50 gallons for a household of 3 individuals.
Consider the Size of Your Household
A large household will automatically require more hot water than a smaller one. Ideally, a home of 1-2 people will need a water heater with a capacity of 30-40 gallons, 3-4 people will require a 50-60 gallon tank, while one with 5-6 people is best served by a tank with a capacity of 60-80 gallons. If you have plans to expand your family soon, it’s smarter to invest in a large tank today than buying a new water heater now and replacing it a few years later.
Sizing a Tankless Water Heater
The shopping journey for a tankless water heater is a little bit different. Instead of heating a large amount of water that is readily available at all times, they heat incoming water only as you need it.  Flow rate (number of gallons used per minute) and temperature rise (total amount of degrees your water will need to be heated before it reaches the fixture) are the key features to look into when sizing a demand-type water heater.
Consult a Professional Plumber in Sarasota
Depending on what you choose, buying a new water heater can be a huge investment, and you need to make sure you pick a unit that meets all your hot water demands. To get the right water heater size, talk to a professional plumber. At Veteran Air & Plumbing, we have a team of fully licensed, experienced, and trustworthy water heater experts who will help you calculate the exact tank size for your home needs.
Whether you need to consult, get an estimate, schedule a tune-up, or replace your old water heater, feel free to get in touch with us.

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