What Size Water Heater Do I Need?

A water heater inside of a home with the words, what size water heater do I need?

If you are constantly timing your family’s showers to ensure that there is enough hot water left for your own, your family probably has the wrong size water heater. When replacing a water heater or buying one for a new home, many homeowners do not know which size water heater they need. This often leads to having an insufficient supply of hot water or the water heater perpetually breaking down from excessive stress. If you are wondering what size water heater would best meet your home’s needs, make sure to keep the following 3 considerations in mind.

1. General Sizing

Generally, the smaller a household, the smaller the water heater you need. Here are some guidelines for accepted sizes of water heaters depending on the occupancy of the household.

  • Smaller homes with 1-2 people generally call for a 30-40 gallon water heater
  • Smaller homes with 2-3 people generally call for a 40-50 gallon water heater
  • Average size homes with 3-4 people generally call for a 50-60 gallon water heater
  • Large families with five or more people call for 60-80 gallon water heater

 2. Actual Sizing

While general sizing will work for some families, others may find that the water heater listed does not meet their specific needs. Each family uses their hot water differently. If you are trying to find the actual size of the water heater that best meets the needs of your home, here are a few things you should take into consideration:

Your Hot Water Habits

To find the right size water heater for your family’s needs, you will want to pinpoint when most hot water is being used during the day. For example, if most of your family is taking showers in the morning between 6 am – 7 am, then this will probably be your busiest hour. Make sure to factor in when you run other appliances as well, such as a washing machine or dishwasher. Running three or more hot water appliances during the same hour suggests that you need a bigger hot water tank than the general size. On the other hand, if you are rarely using more than one hot water appliance within the same hour, you can probably get away with a smaller, more cost-effective tank. It all depends on your hot water habits.

Calculating the Correct Size

Water temperature controls on a hot water heaterRemember, you should be looking for a hot water heater that holds enough hot water to meet your family’s needs. Too small of a unit can leave you constantly fighting for hot water and your unit working harder than it should. This leads to more frequent breakdowns and costly repairs. On the other side of the spectrum, an excessively sized hot water tank can lead to unnecessarily high energy bills.

In order to correctly determine which size is best for you, start with knowing what hour you consumed the hottest water when taking into account all of your appliances. Next, besides each appliance or hot water usage, calculate the typical usage with these general figures.

  • Showers consume 10 gallons of water per usage on average
  • Shaving consumes about 2 gallons of water per usage
  • Washing your hands or hand washing dishes consumes up to 4 gallons of water
  • Running a dishwasher consumes 6 gallons of water per usage
  • A washing machine consumes 7 gallons per usage

Once you have these numbers written down, add them all up. That will tell you how much hot water you need to comfortably make it through your busiest hour.

3. Getting the Timing Right

With your measurements in mind, make sure you pay particular attention to the first-hour rating (FHR) listed on the specifications for each tank. This will tell you how much water will be readily available when you need it. Ensure that your hot water heater has at least 1-2 gallons more than your peak demand. This will help give you a little bit of wiggle room for those instances where you might need a bit more hot water.

Water Heater Testing

Want a more accurate reading of what size water heater you need? Contact the dedicated plumbers at HEB Plumbing & Sprinkler – Kathlyn Smith. We can help you test your water usage and find the perfect size water heater for you. Call us today for all of your plumbing and sprinkler needs!