 |
|
|
|
|
Don Vandervort, Head Homeboy, has written more than 30 DIY home improvement books, been a segment host on HGTV, served as MSN.com's home improvement expert and written countless magazine articles.
|
|
|
|
Capacity of Conventional Gas & Electric Water Heaters |
 Tired of running out of hot water? Maybe it’s time for a water heater that has a greater capacity. But how “big” should it be? Though the term “capacity” refers to a tank’s size, the real capacity of a water heater is a result of two factors: storage and recovery time (how quickly it can heat a tankful of water).
Conventional water heaters range in tank size from 20 to 120 gallons; the most common sizes are 40 to 80 gallons. (Short “lowboy“ models are available in smaller sizes.) It’s important to match size to your family’s needs. If you get a tank that’s too small, you’ll frequently find the water cooling down just about the time you lather up in the shower. On the other hand, if you buy one that’s too large, you’ll be paying more than necessary to keep the tank heated. Needs can typically be measured by the number of bathrooms in the house, though some circumstances can skew these standards—a laundry-heavy family with small children, the overall number of residents in the house, or a house with an especially large bathtub, for example. Obviously, just a couple living in a large house or a large family living in a small house require adjusting the figures.
The minimum size unit for a one-bathroom house should be 30 or 40 gallons, in either a gas or electric model. For a one-and-a-half-bath house, 40 gallons is minimum. For a two- to three-and-a-half-bath house, choose a 50-gallon gas heater or a 66- to 80-gallon electric one (because electric water heaters take longer to heat water, large tanks should be bigger than their gas-fired counterparts). For a large, four-bath house or a home with an extra-large bathtub, get a 75-gallon gas heater or a 120-gallon electric heater.
Recovery of gas-fired water heaters is a function of the BTU input and overall efficiency. Input ranges from about 32,000 on a 30-gallon unit to 88,000 on a 100-gallon tank. A common input is 34,000 BTUs on a 40-gallon tank and 36,000 BTUs on a 50-gallon tank. The higher the BTU input and efficiency, the faster the recovery. Electric water heaters typically have one 5,500-watt or two 4,500-watt elements. Of course, two lower-kilowatt elements still heat much faster than one higher-wattage element.
Both gas and electric water heaters are rated by the number of gallons they can raise 90 degrees Fahrenheit in one hour. Most electric heaters are rated from 20 to 25 gallons per hour; many gas units can recover more than a full tank. A high-recovery 50-gallon Rheem gas model can recover up to 81 gallons per hour. When buying a high-BTU gas model, be aware that it may require a 4-inch flue rather than the standard 3-inch flue that probably currently exists in your house.
Photo courtesy of Whirlpool
|
|
|
|
|
Have a Question About This? |
| | |
|
|
|
|
|
|
|
|
|
|