A water heater s first hour rating fhr is the most important feature to consider when purchasing a new heater since it tells you how much hot water the heater can deliver in an hour of use.
Water heater recovery rate calculator.
Various formulas for water heating calculations efficiency gph x 8 25 x temp.
California flow rate guidelines of fixtures 5 for use in sizing storage and recovery rate requirement of the water heater can be reduced from 445 to 340 gph.
The first hour rating is the number of gallons of hot water the heater can.
Rise x 1 0 btu input gph x 8 25 x temp.
Improving commercial kitchen hot water system performance characterized for its maximum hot water use to calculate the peak hot water demand.
Input specific heat btu output gph x 8 25 lbs gal.
The amount of hot water provided will depend on several things.
The above calculator is for calculating hot water recovery time for hot water cylinders.
Rr hin μ dt ρ p 3413 btu kw dt ρ 3.
Rise x 1 0 btu hr.
If you would like the ability to select higher kw amounts please either feel free to get in touch and tell us or use the formula to calculate it.
To properly size a storage water heater for your home including a heat pump water heater with a tank use the water heater s first hour rating.
Visit the solar water heaters page for more on these calculations.
Sizing storage and heat pump with tank water heaters.
In an electric water heater if the wattage of the elements is 4500 the incoming water temperature is 40 degrees and you are heating the water to 120 degrees temperature rise of 80 degrees the recovery rate is 23 0 gph.
The recovery rate is the amount of hot water the water heater is capable of producing in a given period of time.
However it can be used to calculate general hot water recovery time for any amount of water.