# How do you calculate gpm on a boiler?

**GPM**= Heat Load/ 500 ^T

Also know, what is the formula to calculate GPM?

The formula to find GPM is 60 divided by the seconds it takes to fill a one gallon container (60 / seconds = GPM). **Example**: The one gallon container fills in 5 seconds. 60 / 5 = 12 GPM. (60 divided by 5 equals 12 gallons per minute.)

Also, how do I size a boiler pump? 1 GPM = 10,000 BTU/hr, meaning that for every 10,000 BTU's of heat load the circulator must output a 1 gallon per minute flow. Assuming that system calls for 100,000 BTU/hr, a circulator **pump** should have a minimum 10 Gallons Per Minute flow rate at a given pressure drop.

Beside this, how do you calculate hot water flow rate?

Handy rule: multiply the **hot water flow rate** in litres/minute by the temperature rise in celsius. Divide by 100 and multiply by 7 to get the boiler **DHW** output in kW. Example: 12 litre/min at 40C rise: 12 x 40 = 480.

What is the formula of flow rate?

Q=Vt Q = V t , where V is the volume and t is the elapsed time. The SI unit for **flow rate** is m^{3}/s, but a number of other units for Q are in common use. For example, the heart of a resting adult pumps blood at a **rate** of 5.00 liters per minute (L/min).