Friedrich, ZoneAire Glossary

What’s a Btu?
Air conditioner sizes (or capacities) are rated in Btus (British Thermal Units) per hour. Btus are a measure of the quantity of heat required to raise or lower the temperature of one pound of water one degree Fahrenheit at sea level. Since air conditioners remove heat from indoor air and expel it outside, Btus are the primary measurement used to match your cooling needs with an air conditioner.

What’s an Energy Efficiency Ratio (EER)?
An Energy Efficiency Ratio measures the efficiency of an air conditioner when it is 95°F outside by dividing the Btu/hr of cooling output by the watts consumed. The higher the EER, the more energy-efficient the unit. This ratio tells you the amount of electricity an air conditioning unit requires to provide the desired cooling level.

Federal law requires that a units EER be displayed on a yellow tag so consumers can easily compare energy efficiency of various models. Friedrich models have some of the highest EERs in the industry. See product specific Model Specifications for details.

What’s a Seasonal Energy Efficiency Ratio (SEER)?
SEER measures a systems efficiency over an entire theoretical cooling season and is most often used to evaluate central air conditioners and heat pumps. The higher the SEER, the more efficient the system.

What’s the difference between EER and SEER?
While EER and SEER both measure the energy an air conditioner consumes, there are some differences.

EER (Energy Efficiency Ratio) is associated with demand (or peak) operating conditions. SEER (Seasonal Energy Efficiency Ratio) measures an air conditioner’s theoretical seasonal energy consumption. The higher the SEER, the more energy-efficient the unit.

What’s the ENERGY STAR® program?
ENERGY STAR® is a joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy. Its purpose is to help consumers and businesses reduce energy consumption, save money and protect the environment with energy-efficient products and practices. Air conditioners can earn the ENERGY STAR® label by meeting the energy-efficiency requirements set forth in ENERGY STAR® specifications, which require that a unit be at least 10% more efficient than the DOE minimum performance level. Friedrich is proud to be a founding partner in the ENERGY STAR® program. We offer numerous ENERGY STAR® qualified models.

What is a Heat Seasonal Performance Factor (HSPF)?

Heat Seasonal Performance Factor measures the efficiency of heat pumps. Higher HSPF ratings mean a system is more efficient. Like SEER, HSPF measures seasonal performance.

What is a Coefficient of Performance (COP)?
COP is the ratio of the heat produced by a heat pump to the energy it consumed to produce that heat. It is most often used to evaluate central air conditioners and heat pumps. The greater the coefficient of performance, the higher the units efficiency.

What is a Heat Pump?
A heat pump is an all-in-one heating and air conditioning system that works year round to keep you comfortable. During warmer months a heat pump works as an air conditioner by extracting heat from inside the home and transferring it outdoors. In colder weather the process reverses, the unit removes heat from the outdoor air and transfers it inside your home. Even when the outside air feels cold it contains some heat. When there’s not enough heat in the outside air to reach the thermostats setting, the supplemental electric heater, available on several models, warms the home. Heat pumps can be extremely efficient but work best in moderate climates where outdoor temperatures remain on average above 45 degrees F in winter.