Water Tanks Decoded
The fun and excitement that comes with buying a new water tank rivals that of emergency dental surgery, tax audits and tetanus shots. That is to say, welcome to adulthood—but fear not. Let’s learn about gas and electric storage water tanks.
Averaging a 12-year lifespan, that tank in your basement likely will buy the farm before you do. Do not go gentle into that good night. This glossary o’ terms will take you from zero to WTF—that’s Water-Tank Fluent—in no-time flat.
Second to home-heating costs, conventional storage-type water heaters (gas and electric hot-water tanks) account for 14 percent to 18 percent of your home’s utility bills, according to the U.S. Department of Energy. That’s up to a whopping $600 a year.
The Energy Factor measures water heater efficiency based on the amount of hot water produced per unit of fuel consumed in a 24-hour period. I’ll spare you from the formula. The federal minimum EF for electric tanks is EF .95; for gas, it is EF .60. That means an electric tank must turn at least 95 percent of its energy intake into usable hot water.
Energy Factor in Real Life (IRL): More hot water for less money. The higher the EF the better.
Energy Guide: It’s the yellow sticker on every tank. This federal program’s iconic yellow label denotes model number, capacity, Energy Factor and a graph showing its annual operating cost in range with similar models.
A FHR is the gallons of at-temperature water a fully heated tank dispenses within an hour. At-temperature water is 20 degrees less than or equal to a 120° F, generally.
First-Hour Rating IRL: Sounds like: WHO USED ALL THE HOT WATER? FHR is how much water you can use before it dips below 100° F.
A tank’s heaviest one-hour usage period(s), when it experiences greatest demand.
Peak-Hour Demand IRL: This is when your household decides to take a shower, do dishes, start a load laundry and water the plants. Simultaneously. Sounds like: WHO FLUSHED THE TOILET?
|Use||Average gallons of
hot water per usage
during 1 hour
in 1 hour
|Shower||10 gal.||x||2||=||20 gal.|
(.05gpm @ 4 min.)
|2 gal.||x||1||=||2 gal.|
(2gpm @ 2 min.)
|Automatic Dishwasher||6 gal.||x||1||=||6 gal.|
|Clothes-Washer||7 gal.||x||1||=||7 gal.|
The number of years it will take for a unit’s energy savings to offset its purchase price. Look for a payback period of 10 years—the general lifespan of a hot water heater.
Payback Period IRL: This comes into play when two units have the same First-Hour Rating but are different prices. Is it worth paying more? This formula will tell:
Starting with a cold tank o’ water, this is how many gallons of hot water you’ll have within an hour.
Recovery Rate IRL: This is the irritating hour following Peak-Hour Demand. Sounds like: Quietly sulking until the water’s hot again.
Standby loss is the amount of energy used maintaining a tank’s water temperature. Standby loss is greater in gas units, with insulation only on the tops and sides.
- CALCULATE your home’s Peak-Hour Demand using the calculator. This is really important stuff, folks.
- MATCH your new tank’s First-Hour Rating (on the Energy Guide label) meet your home’s Peak-Hour Demand.
- MEASURE your current tank’s physical size and footprint.—getting it right is half the battle.
- SHOP for a unit that meets your needs—and don’t worry. One of our amazing plumbing experts, like Diane, will take great care of you. We’ll special order anything, from a goldfish to a 200-gal. water tank. Really.
Keep the good times rollin’! Sign up for emails and get advanced notice on sales, in-store deals, events and more. Plus, catch up on the latest blog posts!