Consider if the size of your present heater satisfies your demands if a new water heater is in your near future.

You may complete the procedure with these expert advice.

Q: Our water heater is beyond repair.

The water flowing out of the tank is no longer hot despite my efforts to raise the temperature to its maximum level.

It is thus time to get a new water heater! The 30-gallon size of our current tank was enough when we purchased the home ten years ago, but as our family has expanded, we are now consuming more water for bathing and doing laundry.

How big of a water heater do I require?

A: It seems like you will need a bigger water heater this time.

Additionally, you are correct in that larger families use more water.

According to Daniel O’Brian, the technical specialist at online plumbing shop, “the number of users is crucial for tank-style water heaters since the output is more or less fixed.” O’Brian offers advice on choosing the right size water heater depending on whether you want to replace your old unit with a tank or tankless type.

Household size is a straightforward predictor of hot water requirements for a tank-style heater.

Based on the number of occupants in the residence, you may determine the required tank capacity (in gallons):

  • 1 or 2 people—23 to 36 gallons
  • 2 to 4 people—36 to 46 gallons
  • 3 to 5 people—46 to 56 gallons
  • 5 or more people—over 56 gallons (add 10 gallons per additional person)

A 40-gallon water heater, such as the ProLine Power Vent Gas Water Heater by A. O.

Smith (available at SupplyHouse), should be enough for the typical household of four.

However, it shouldn’t be your only factor.

By looking a bit closer, you can determine your family’s hot water requirements.

Take into account a water heater’s first hour rating in addition to tank capacity.

When a tank is completely heated, its first hour rating (FHR) indicates how much hot water it can generate in that time.

This number represents the efficiency of the device (how fast the water heater can reheat the water) and provides a rough estimate of its capacity during peak consumption. A. O.

Smith’s 50-gallon ProLine Power Vent Water Heater, for instance, has an FHR of 90 gallons and can heat up to 90 gallons of water in an hour.

It is available through SupplyHouse.

You should search for an FHR that can provide at least as much hot water as is required for all concurrent activities during the busiest time of the day.

You can anticipate peak hour consumption and choose the appropriate FHR by using the data below.

  • Bathing or showering (per person)—20 gallons
  • Washing hair (per person)—6 gallons
  • Washing hands (per person)—2 gallons
  • Washing dishes by hand—6 gallons
  • Shaving—3 gallons
  • Running dishwasher—14 gallons
  • Running clothes washer—30 gallons

Consider a tankless heater if a bigger tank won’t fit in the present area.

According to O’Brian, “tankless heaters, which are often wall-hung, may fit in narrower locations” since they don’t have a large storage tank.

A 50-gallon tank water heater, for instance, may measure up to six feet tall and 22 inches in diameter.

The Takagi Tankless Natural Gas Water Heater (available from SupplyHouse) is one tankless alternative with a similar output, however it is just 20 inches high, 14 inches wide, and less than 10 inches deep.

A tankless water heater may be the best option if space is at a premium.

Calculate the needed flow rate based on hot water demand and the desired temperature change to choose the best tankless water heater.

Hot water is not kept warm by tankless water heaters.

They instead heat it as required.

According to O’Brian, “Flow rate is the crucial specification for sizing a tankless water heater.” You may estimate the flow rate requirements for your family using the information below.

  • Sink faucet—1 gpm
  • Bathtub—3 gpm
  • Shower—2.5 gpm
  • Dishwasher—3 gpm
  • Clothes washer—3 gpm
  1. A tankless water heater with a minimum flow rate of 5.5 gpm is required if, for instance, your peak consumption period is right after dinner when you’re running the dishwasher and having a shower at the same time (3 gpm + 2.5 gpm).
  2. The temperature of the water entering your home should then be determined. Simply turn on a cold water faucet, let it run for a few minutes, and then check the temperature of the cold water using a thermometer.
  3. To calculate the necessary temperature increase, deduct the cold water’s temperature from 110 degrees Fahrenheit, the typical home hot water temperature. The needed temperature increase, for instance, is 45 degrees Fahrenheit if the cold water is 65 degrees Fahrenheit and the water heater has to heat the water 45 degrees Fahrenheit to get it to 110 degrees Fahrenheit.
  4. Depending on the necessary temperature increase, adjust the flow rate. According to O’Brian, “all units should include a chart that depicts the flow of hot water at different temperature increases.” The Takagi T-D2-IN Natural Gas Tankless Water Heater, for instance, has a maximum flow rate of 10 gpm (the crucial term is “maximum”). It is available at SupplyHouse. The Takagi has an effective flow rate of 10 gpm in warm climates when a temperature increase of just 20 degrees is required. However, as shown on the flow rate chart given by the manufacturer, the flow rate drops to roughly 7 gpm if you require the water heater to increase the water’s temperature by 45 degrees Fahrenheit.

What Size Water Heater Do I Need Videos Suggestions From Youtube

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Written by Bob Matsuoka
Bob Matsuoka is a blogger and founder of RVing Beginner blog. He has been blogging for over five years, writing about his own family’s RV adventures, tips for people who are interested in buying an RV or taking their family on an adventure by RV.