Water heaters generally come in sizes between 20 gallons and 80 gallons. It’s essential to pick a water heater of the right size because one that’s too small will wear out too fast while one that’s too big will run your energy bill up quite a bit.
How to Pick the Right Size
For one or two people, a 40-gallon tank will be just about right. For three to five people, an 80-gallon tank is good. For six or more people, you’ll either need multiple tanks or a larger tank. Above 80 gallons, a good rule is 10 extra gallons per person.
It’s also important to considerthe tank’s “first-hour rating.” The FHR indicates how much hot water the tank can produce in an hour. The FHR can be bigger than the amount of water the tank can hold. The rating includes using some of the hot water and then heating the water that replaces what’s first used. For example, it’s possible for a 50-gallon tank to have an FHR of 90, meaning that it can provide hot water up to nearly double its size in an hour. After that, though, the hot water will have run out.
To be a little more specific about the size of tank you need, you can use the following amounts of water to guess how much you’ll use in a typical day:
- Shower: 20 gallons per person
- Laundry: 30 gallons per load
- Dishwasher: 14 gallons per load
- Dishes by hand: 6 gallons
- Shaving: 3 gallons per person
- Brushing teeth: 3 gallons per person
- Hand washing: 2 gallons
- Toilet flush: 2 gallons
- Old toilets: up to 7 gallons
As you can see, a family of five with teens could easily use between 300 gallons and 500 gallons in a day. That family would need at least an 80-gallon tank if not 100 or more.
Other Considerations
Will you choose a tank powered by gas or by electricity? Will you even choose a water heater with a tank? Tankless water heaters are more expensive up front, but they can save you up to more than 30% on your monthly bill. It’s a balance. Tankless water heaters are measured by their flow in gallons per minute. Usually, a good formula is 2 gallons per minute per person for an average household. Active households will need a bigger flow rate while relaxed households could probably make do with a little less.
The Right Stuff
At Benjamin Franklin Plumbing, you’ll find top-flight products, exceptional workmanship, and stellar customer service. After all, we’ve been in the business for almost 40 years, so you can trust our experience. Call us today to make an appointment.