Choosing the right water heater for your home is an important decision. If you select a unit that’s too small, you’ll be inconvenienced by long waits for hot water and may see the heater work itself into an early retirement. If you go too big, you’ll spend more than you should have with no benefits to show for it.
To zero in on the right size water heater for you, you will need to have a good understanding of how water heaters work and how to assess your family’s water consumption habits. Let’s get started on it!
Start with the Size of Your Family
The biggest variable that determines the size water heater you need is the number of people in your home. More people means more showering, more laundry, more handwashing, and so on. Because many of those activities take place in several rounds back to back, it can be pretty taxing for your water heater. Imagine five kids getting showers before school every morning, and you’ll understand this point very quickly!
However, there can be some other dimensions to this number. You may only have four people living in the home, but what about company? Do you frequently have people come visit overnight, host pool parties for the kids, or just have big dinners with the extended family? Even your four-legged family members will increase the water demand in your home if you’re regularly bathing a large dog or two.
Determine Your First Hour Demand
Water heaters heat up water, then store it in the amount stated in the size of the unit. In other words, a 40-gallon water heater has 40 gallons ready for your use. Once that full amount has been used up, you need a water heater that will take about an hour to replenish the stockpile of hot water. That’s what we’re talking about when we say “first hour rating”. The idea is to determine how much water you’ll use in an hour, then find a water heater with a FHR of at least that amount.
Now all you need to do is figure up what your first hour consumption is. It takes about 20 gallons for a shower, followed by three gallons if you shave afterwards. Proper handwashing takes two gallons, and running the dishwasher fifteen (six if you wash the dishes by hand). As far as laundry, top-load washers use about 30 gallons per load, while front-load models consume a little bit less.
So if a family of four all gets up on a work day and each member takes a shower with two members shaving afterwards, they are at about 86 gallons in that first hour. They should purchase a water heater that can handle that amount of water in an hour.
You should also consider the length of showers your family members take. You may have some in your family who regularly get very dirty at work, or who have long hair that requires long showers. Others may take long showers just because they like long showers, while some may make a daily effort to shower quickly. Take these kinds of factors into account as you figure up your first hour demand.
Don’t Forget to Measure!
It should come as no surprise that water heaters with a bigger capacity will take up more space in your home. Whether you’re replacing an old water heater or working through construction of a new home, you need to make sure that there is enough room for the water heater you’re planning to install.
For replacement water heaters, Benjamin Franklin Plumbing reminds us that your previous unit may have been installed before changes to the building code that may now include additional features like an expansion tank to absorb excess pressure that can develop if something goes wrong. Be sure that your space has room not just for the new heater itself but also for these safety provisions.
Whatever may be cramping your space, it’s best to find a way to add space than to go with a smaller water heater. You may need to have pipe lengths adjusted or even consider relocating a wall. Whatever modifications need to be done, be sure they comply with code and allow for the water heater that you really need.
In a Few Words…
This guide should have you well prepared to get started on the process of selecting a new water heater. Just remember these basic points:
- How many people use your water?
- What are your habits?
- What special factors are in play?
- What adjustments will be necessary for a good fit?
With this simple guide, it will be easy to choose a water heater that meets your needs.