Enter the power in BTU/hour and the temperature difference in degrees Fahrenheit into the calculator to determine the hydronic flow rate in gallons per minute (GPM).
Hydronic Flow Formula
The following formula is used to calculate the hydronic flow rate:
Flow Rate (GPM) = Power (BTU/hour) / (ΔT (°F) * 500)
Variables:
- Power is the heat transfer rate in BTU/hour.
- ΔT is the temperature difference across the hydronic system in degrees Fahrenheit.
- Flow Rate is the volume of water flow in gallons per minute (GPM).
To calculate the hydronic flow rate, divide the power by the product of the temperature difference and 500.
What is Hydronic Flow?
Hydronic flow refers to the movement of water or another liquid through a hydronic heating or cooling system. This flow is necessary to transport heat energy from the source to the destination, such as from a boiler to radiators or from a chiller to cooling coils. The flow rate is a critical factor in ensuring the system operates efficiently and effectively, providing the desired temperature control within a building or space.
How to Calculate Hydronic Flow?
The following steps outline how to calculate the Hydronic Flow Rate.
- First, determine the power (heat transfer rate) in BTU/hour.
- Next, determine the temperature difference (ΔT) across the hydronic system in degrees Fahrenheit.
- Use the formula from above to calculate the Flow Rate (GPM).
- Finally, calculate the Hydronic Flow Rate in gallons per minute (GPM).
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem:
Use the following variables as an example problem to test your knowledge.
Power (BTU/hour) = 15,000 BTU/hour
Temperature Difference (ΔT in °F) = 20°F
