Enter the airflow rate (CFM), the temperature difference between the air after recovery and the air before recovery (F), and the heat recovery efficiency (%) into the Heat Recovery Calculator. The calculator will evaluate the Heat Recovery. 

Heat Recovery Formula

The following formula is used to calculate the Heat Recovery. 

HR = 1.08 * Q * dT * E/100

Variables:

  • HR is the Heat Recovery (BTU/h)
  • Q is the airflow rate (CFM) 
  • dT is the temperature difference between the air after recovery and the air before recovery (F) 
  • E is the heat recovery efficiency (%) 

How to Calculate Heat Recovery?

The following steps outline how to calculate the Heat Recovery.


  1. First, determine the airflow rate (CFM).
  2. Next, determine the temperature difference between the air after recovery and the air before recovery (F). 
  3. Next, determine the heat recovery efficiency (%). 
  4. Next, gather the formula from above = HR = 1.08 * Q * dT * E/100.
  5. Finally, calculate the Heat Recovery.
  6. 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.

airflow rate (CFM) = 100

temperature difference between the air after recovery and the air before recovery (F) = 30

heat recovery efficiency (%) = 50

HR = 1.08 * Q * dT * E/100 =  ?