Water Heater Selection Guide

Water Heater Selection Guide

To select the right water heater for your home, you need to consider the size of your family and other factors that contribute to your First Hour Rating Requirement. The chart below provides residential water heater selection guidelines for several family sizes.

To Choose the right water heater for you...

  1. Determine whether your family is Low Demand or High Demand. You should consider your family to be high demand if...
    • There are more than two full baths in the home.
    • There are (or will be) teenagers living in the home, It's a fact: teenagers use more hot water for showering or washing clothes.
    • If you have an oversize whirlpool bath or other large tub. As a rule of thumb, the water heater tank capacity should be 100% of the bathtub capacity (example: 75 gallon tub/75 gallon water heater).
  2. Find your family size and Demand Profile in the chart below, and read across to find the first hour rating requirement for your family. If you decide your family is high demand, consider moving up to the next first hour rating level.
  3. Find the water heater with the first hour rating that meets your requirement.

Family Size
First Hour Rating Requirement
2 people
45-55 Gallons
3 People
55-65 Gallons
4 People
65-75 Gallons
5 People
75-85 Gallons
6 People
85-100 Gallons
7 or more people
100 or more gallons