For an instantaneous hot water unit servicing two water saving shower heads you would need a hot water heater with a flow rate of at least 16l min.
Water tank size for family of 4.
With these two figures combined with your catchment area and water usage we can now calculate the optimum size for a water tank to suit your needs.
Choose a hot water heater with a tank size in the range of 50 to 60 gallons on the fhr label.
For a tank style heater household size is a simple indicator of hot water needs.
This is probably one reason why our 5 000 gallon 22 500 litre tank and 5 400 gallon 24 500 litre tank outsell all other sizes.
Storage tank hot water heaters are sized based on btu input and capacity in gallons.
Taking a 4 person household for example located in rural victoria with 452 litres usage a day and an average roof area of 200m2 we can head over to the alternative technology association s tankulator tool.
Again the more you rely on hot water on a regular basis the more btus and capacity you ll need.
You can estimate the necessary tank capacity in gallons based on the number of people in the house.
If your family size is 5 or more you ll need an 80 gallon tank electric or a 50 gallon tank natural gas or liquid propane.
1 or 2.
A hot water tank size for family of 5 would be in the 230 300l range 60 80 gallons.