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What Size Water Heater Do I Need?

Choosing the right size water heater is important. Too big and your energy bill will be sky-high. Too small, and it will be nearly impossible for your home to get enough hot water.

Read on to learn how to assess all the hot water heater sizes and figure out the answer to the question: What size water heater do I need?

Ready to be done with cold showers? Upgrade your water heater by calling Mr. Rooter® Plumbing at (855) 982-2028.

Hot Water Heater Types Explained

Before we discuss water heater sizes, you need to understand the three main types of residential water heaters that are available on the market to choose from. Each type of water heating system has its own benefits, drawbacks, and price points, and choosing the right system can make a huge difference for your household’s hot water demands.

The three types of water heaters are:

  • Storage Tank Water Heater
    This is the most common type. These traditional water heaters have an insulated tank that stores hot water until needed. Electric and gas models are available. Overall, they feature low upfront costs and are suitable for larger households. Gas models tend to cost a little more to purchase, but most homeowners find the operating cost to be less than that of electric models.
  • Tankless Water Heater
    This newer type of water heater is typically more expensive up front, but more energy-efficient in the long run. Gas and electric models are available to produce hot water on demand, but they can only supply a limited amount of hot water per minute.
  • Solar Water Heating System
    This type of water heater includes a storage tank and a solar collector. There are two types of solar water heating systems to choose from: active solar water heating systems, which have circulating pumps and controls; and passive solar water heating systems, which do not use pumps or controls.

Each type of water heater has its own sizing requirements. To size a tankless water heater, you need to determine the flow rate and the temperature rise you'll need for its application in your home. To size a solar water heating system, you will need to hire a professional to determine system requirements and collector sizing.

Calculating Your Ideal Tank-Style Water Heater Size

So, what size tank-style water heater do you need for your home? The recommendations vary from household to household.

The general rule of thumb says a one or two-person household needs a 30- to 40-gallon water heater. Three or four people need a 40- to 50-gallon water heater. With five or more people in the house, nothing smaller than a 50-gallon water heater will do. There are larger water heaters than that, but they are rarely installed in residential homes.

To find out how many gallons your current water heater holds, look for the manufacturer's label on the side of the water tank. That will tell you how many gallons your current water heater holds, and that should help inform your decision about the size of your future water heater.

Call Mr. Rooter, the Water Heater Experts

Your local Mr. Rooter can help you calculate what hot water heater size is ideal for your needs. We can also perform water heater replacements, including tankless water heater upgrades for an infinite hot water supply. You can trust our licensed plumbers for satisfactory service, and you’ll love our upfront pricing. Call us today at (855) 982-2028 or request your estimate online!