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5. Calculate Heating Degree Days and Cooling Degree Days
A heating degree day (HDD) is each degree that the average daily temperature is below the base temperature (65 degrees F) is one heating degree day.
A cooling degree day (CDD) air temperature differences between the outdoors and 78 degrees F over the summer season.
Heating degree days and cooling degree days are used by energy professionals around the world for several reasons:
Heating Degree Day and Cooling Degree Day Formulas
Balance point of HDD = 65 degrees
Balance point of CDD = 78 degrees
The HDD is a tool for predicting heating costs.
Example: Today's temperature was 10 degrees as a low and 40 degrees as a high. What is the HDD?
3a. Applied diagnostics and troubleshooting