However every family has different water demand requirements.
Water heater room size.
2 3 people you ll need at least a 40 gallon capacity tank.
1 2 people you ll need a water tank with at least a 30 gallon capacity.
Once you have your total flow rate and the required temperature rise you can find the right size tankless water heater for your home.
Below we ve highlighted what size water heater you would need in our example of 6 5 gpm at a 63 f temperature rise.
You can estimate the necessary tank capacity in gallons based on the number of people in the house.
The good news is that just by following a few guidelines you can find the perfect size water heater.
Determine the home s fhr or first hour rating.
X 10 1200 watts.
Usually most homeowners find that either a 40 or 50 gallon hot water tank is the best fit for their needs.
For a tank style heater household size is a simple indicator of hot water needs.
Consequently these are the two most frequently installed sizes.
Room for example requires a 1200 watt space heater 120 sq.
That s the measure of how much hot water the heater will deliver during a busy hour such as first thing in the morning.
This is the quickest and easiest way to size a space heater but unfortunately there are a number of factors that can throw it off and have to be taken into account.