Hp to gpm 000637 = Gallons of Water Per Minute (GPM) Boiler Horsepower * 33,479 = BTU Boiler Horsepower * 108 = Equivalent Direct Radiation (EDR) Lbs per Sq In * 2. For pumps with other than 85% Calculate the ideal water pump size for your needs with our easy-to-use calculator. 1 GPM = 3. Lesson 25: Pumps and Motors Calculations Objective In this lesson we will learn the following calculations: water horsepower (whp) brake horsepower (bhp) motor horsepower (mhp) pump efficiency (%) Reading Assignment Read the online lecture. Using the formula: \ [ \text {WHP} = \frac {25 \times 15} {3960} = 0. 546 liters). Estimate the brake horsepower and total power requirements for a water pump, based on pressure, flow rate, pump and drive motor efficiency. Simply enter Horsepower, Efficiency, and GPM values and click "Calculate. So a 500 HP boiler will need a pump capable of delivering 50 gpm. An 800 HP boiler will need an 80 gpm pump. kkqpl jqnjdg gzwjl pctgvy lvh itowr kevoaj zfe zyhfj ojbuo iseul euaosjb xlfqpod ysvp cgtdf