Tips for Choosing the Right Size Water Heater for Your Home

Sizing a water heater for your Plainfield, Illinois, home is not always easy. Your water heater will last a decade or more, representing a sizable financial investment. You want to avoid the common mistakes people make when sizing their water heater so that you can have sufficient hot water for your home for years to come.

Avoiding Common Mistakes When Sizing a Water Heater for Your Home

A common mistake homeowners make when they try to size a water heater for their home is over-sizing or under-sizing it.

If you undersize your water heater, you will run out of hot water as you shower, wash your laundry, or do other daily activities. For example, a 30-gallon water heater for a family of five is generally considered to provide 50% of the water heating capacity you need.

Getting a unit that is too big means you will waste a lot of energy heating water you will not use. For example, 60 gallons of water for a family of two is about one-third more water heating capacity than you need. Getting a unit that is too big means you will spend hundreds of dollars on the unit itself and waste valuable space in your home.

The key to avoiding these mistakes is having your water heater sized adequately by experienced HVAC and plumbing professionals like TR Miller Heating, Cooling & Plumbing. Our team will meet with you, evaluate your water heating needs, and help you find a unit that will work well for you today and for years.

Factors to Consider When Sizing a Water Heater

Because of how important it is for you to get the right size water heater, you want to consider all the factors that affect hot water use in your home. This includes the size of the home or building you need hot water for, the number of people in the family or the number of people occupying the building, and your estimated peak hot water hourly demand.

You must be familiar with water heater capacity and peak hour hot water demand. This will make it easier for you to understand tables with water heater sizes based on building occupancy.

What Is Water Heater Capacity Rating?

Water heating capacity rating is a critical metric that helps technicians adequately size the water heater for your home or commercial building. You may see 30-gallon, 50-gallon, or 60-gallon heaters, which refer to water heaters’ capacity ratings, or in other words, the amount of hot water a water heater can produce within the first hour if you start with a full tank of water.

The Federal Trade Commission (FTC) makes it easy to identify the water heater capacity rating because they mandate that this information be included on the EnergyGuide label.

A general guideline for water heater in sizing is First Hour Rating (Heater Capacity) ≤ Peak Hour Demand (usually one hour when you shower). Your water heater should be large enough to provide one hour of hot water for a shower.

You can think about this in practical terms. Let’s say in the morning, from 6 a.m. to 7 a.m. that three people need to take a shower. According to US Energy Saver, a typical shower uses 20 gallons of hot water. In this scenario, you will need a 60-gallon water heater or larger.

After the first hour of usage, when the tank starts full of hot water, you have to think about other factors when determining how efficient the hot water tank would be. These include tank capacity, heat source, and size of heat source.

A water heater will produce less hot water in its second and third hours compared to its first hour, starting with a full hot water tank. For example, if you start with a 50-gallon water heater, you will enjoy 50 gallons of hot water during the first hour. However, during the second hour, depending on the heat source and the size of the heat source, you may get between 16 and 20 gallons of hot water because the heating element has to work to reheat the water in the tank.

How to Determine Your Peak Hour Demand

Determining the peak hour demand for your water heater is a crucial step. To do this, try to estimate the amount of hot water you will require when your family uses the most water. This is typically when everybody takes a shower. This is the size water heater you should purchase. You may want to add a couple of gallons for when someone might take an exceptionally long shower, etc.

Although this is not set in stone, general water heating needs based on the size of a family are as follows:

  • A family of one needs 25 gallons.
  • A family of two needs 35 gallons.
  • A family of three needs 45 gallons.
  • A family of four needs 55 gallons.
  • A family of five needs 65 gallons.
  • A family of six needs 75 gallons.

Calculating all the everyday activities that require hot water that your family engages in simultaneously is vital. For example, you can factor in 20 gallons per shower, three gallons for washing your hands, 5 gallons for brushing your teeth, 25 gallons for washing clothes in a washing machine, and around two gallons for shaving.

For example, let’s say you have a family of four in a house with two bathrooms. From 7 a.m. to 6 p.m., three people will shower, one person will shave, and everyone will brush their teeth. During the peak hour, you have 60 gallons for the three showers, two gallons for shaving, and four gallons for brushing your teeth, which would be 64 gallons of hot water usage during peak hours.

You will need a water heater that has a minimum 64-gallon capacity. It is preferable to overshoot and get a 70-gallon water heater instead of a 60-gallon water heater. An 80-gallon heater will mean wasted space, wasted money spent on the unit, and unnecessary energy to heat water that you probably will not use.

The three fundamental principles to remember when sizing a water heater are the size of the family, the average use of hot water per person, and a baseline of 15 to 20 gallons of water for maintaining and cleaning the house. By sticking to these three basic principles, our team of technicians at TR Miller Heating, Cooling & Plumbing will find the right size water heater for your home.

HVAC and Plumbing Problems Solved Right the First Time in Plainfield, Illinois

At TR Miller Heating, Cooling & Plumbing, we are experienced HVAC technicians and plumbers who have served the greater Chicago area for nearly two decades. We are members of ACCA, and our technicians are NATE-certified. We pride ourselves on offering emergency service and straightforward pricing.

Our services include HVAC repair, installation, and maintenance. We offer radiant heating services, burst pipe repair, drain cleaning, bathroom remodeling, slab leak repair, gas leak detection, and more. Contact TR Miller Heating, Cooling & Plumbing today to enjoy no-hassle service.

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