Choosing Water Heater Size

When it is time to select a new water heater for your property, it is important to pick one that is the right size for your home and the number of residents who live inside. If the water heater is too big then you will the waste energy and water you don’t use. If the water heater is too small, when someone takes a shower it is likely they will run out of hot water midway through.

Calculate the home’s first hour rating, or FHR. The FHR tells you how many gallons of hot water the unit can produce in an hour of high use. This will give you a good idea on how big of a tank you should get.

To Calculate FHR;

1. Take the number of people in residents
2. Multiply by 12

An average of 12 gallons per person is the recommended amount of water you should account for each member of the household to use.

Let’s say there are four people who reside inside your home. Take 12, the number of gallons one will use. Multiply by four, the number of residents in your home to get 48. This number represents how many gallons your tank will need to be. Select a tank that is a few gallon within the number you calculated for a good sized tank for your home and family.

Electric models do not have as high FHR as gas and oil units. Water is heated faster by a flame than other sources. If you calculate a number larger than 100 it might be a good idea to install an additional water heater. This will ensure all residents in your home will be provided with the amount of hot water they need.

After 10 years, your water heater might need to be replaced. Take into consideration how the number of residents inside your home has changed over the years. This can change and helps to determine what size water heater will be best for your home. As a homeowner, you do not want to waste money on energy and water that will go unused.