Seasonal energy efficiency rating, abbreviated as SEER, also called seasonal energy efficiency ratio, a dimensionless number, measure the efficiency a residental central cooling will operate over an entire cooling season.
 seasonal Btu of cooling
 seasonal watthours used
Seasonal Energy Efficiency Rating Index
Seasonal Energy Efficiency Rating (Varying Weather Conditions) formula

\( SEER \;=\; 1 \; ( EER \; 100\% ) + 42 \; ( EER \; 75\% ) + 12\; ( EER\;250\%\ ) \;/\;100 \) 
Symbol 
English 
Metric 
\( SEER \) = seasonal energy efficiency rating (varying weather conditions) 
\(dimensionless\) 
\( EER \) = energy efficiency rating 
\(dimensionless\) 
Seasonal Energy Efficiency Rating (EER above 14) formula

\( SEER \;=\; EER \;/\; 0.875 \) (Seasonal Energy Efficiency Rating (EER above 14))
\( EER \;=\; SEER \; 0.875 \)

Symbol 
English 
Metric 
\( SEER \) = seasonal energy efficiency rating (when EER is above 14) 
\(dimensionless\) 
\( EER \) = energy efficiency rating 
\(dimensionless\) 
Seasonal Energy Efficiency Rating (EER below 14) formula

\( SEER \;=\; 1.12  \sqrt{ 1.2544  EER \; 0.08 } \;/\; 0.04 \) 
Symbol 
English 
Metric 
\( SEER \) = seasonal energy efficiency rating (when EER is below 14) 
\(dimensionless\) 
\( EER \) = energy efficiency rating 
\(dimensionless\) 