How they work: Tank water heaters typically hold between 20 and 80 gallons of hot water (around 120 degrees Fahrenheit) in a storage tank. They are fairly large and require a bit of space within ...

For Tank Water Heaters: A 30-40 gallon tank is usually enough for 1-2 people, a 40-50 gallon tank works for 3-4 people, and larger households might need a 50-80 gallon tank.