How to Size Your New Hot Water Heater | Water Heater Installation in Atlanta

Is it time to replace the hot water heater in your Atlanta home?

When selecting a water heater, it’s important to choose the right size for your home and your family. Choose one too big and you’ll see the impact on your utility bills each month. Choose one too small, and it won’t provide enough hot water to meet your needs.

So how do you know the proper size hot water heater to install?

Tank Water Heaters

Traditional tank water heaters need to hold enough water in their tank to meet your household needs. To determine what size tank you need, look to the FHR rating – first hour rating.

FHR is based on the number of people within the household, and the family’s peak demand. To calculate FHR, a simple rule of thumb is to add the number of bedrooms in the home plus one. So for a three bedroom home, four would be the result. Then multiply this by 12 gallons. In this example, this three bedroom home would have an FHR of 48 gallons.

Typically family breakdowns are:

1-2 people need a 30 gallon hot water heater
2-3 people need a 40 gallon hot water heater
3-4 people need a 40-50 gallon hot water heater
5 or more people need a 50-80 gallon hot water heater

Keep in mind that your household needs also come into play. Do you work out of your home? Do you have a hot tub or soaking tub you use daily? Special needs can alter your numbers, adjust accordingly.

Tankless Water Heaters

Tankless water heaters aren’t measured in gallons stored, but instead in flow rates. A tankless water heater’s flow rate should equal the peak demand used by your family.

To determine your family’s needs, list the water devices you use together on a regular basis. Then add up the flow rate of each fixture. Your tankless water heater should have a flow rate equal to the number you arrive at. If a model has a flow rate of 3.5 gallons, for instance, this would be enough for an average shower and sink faucet to operate simultaneously.