Usually most homeowners find that either a 40 or 50 gallon hot water tank is the best fit for their needs.
Average water heater size gallons.
In this instance you would need a water heater with a first hour rating of at least 72 gallons before you run out of hot water during that 1 hour period.
For a tank style heater household size is a simple indicator of hot water needs.
Sizing storage and heat pump with tank water heaters.
Consequently these are the two most frequently installed sizes.
Assuming your water temperature is 40 coming into your home and you want to produce enough hot water to run 2 showers at the same time what temperature rise would you need to produce to accomplish this.
An average shower will be between 104 106 and uses 2 6 gallons of water.
For 1 to 2 people.
Utility water heaters usually range in size from 2 5 to 19 gallons.
Well to get an accurate answer you d have to calculate out how much hot water you typically use during your busiest hot water using hour.
The first hour rating is the number of gallons of hot water the heater can supply per hour starting with a tank full of hot water.
Typically residential water heater sizes range from 40 to 100 gallon tanks.
This tank size based on the scenario in step 2 is adequate for the peak hourly hot water requirements.
A tankless water heaters flow rate should be equal to your family s peak demand.
30 40 gallons for 2 to 3 people.
You can estimate the necessary tank capacity in gallons based on the number of people in the house.
In most cases you would need a 50 gallon tank water heater in this situation considering most 40 gallon models have a lower fhr.
To determine what size tankless water heater.
If you re going with a storage tank water heater here s a rough guide for storage tank capacity.
1 2 people you ll need a water tank with at least a 30 gallon capacity.
Together that equals 72 gallons of hot water needed.
Tankless water heaters capacities aren t measured in gallons stored but in flow rates.
2 3 people you ll need at least a 40 gallon capacity tank.
Choose a hot water heater with a tank size in the range of 50 to 60 gallons on the fhr label.
Small storage tank water heaters known as point of use or utility water heaters are good choices for adding hot water to outbuildings shops or garages.
What size water heater do i need.
But if you only need a loose estimate of what size you need versus an exact calculation follow these guidelines.
3 4 people need a 40 50 gallon water heater.