Cooling Efficiency – What Do The Numbers Mean?

Cooling Efficiency – What Do The Numbers Mean?

Cooling efficiency plays a big role in the comfort of your home. The more efficient your cooling system is, the more comfortable your home will be. As an added benefit, you’ll also save money because an efficient cooling system doesn’t work as hard as an inefficient one.

A confusing set of measurements – EER and SEER – describe cooling system efficiency. What are these numbers and what do they tell us? The efficiency of any system compares what you get out to what you put in.

EER. The Energy Efficiency Ratio (EER) compares the cooling output in BTUs to the energy input in Watt-hours. It tells you how much energy a cooling system uses over one hour using precise temperature and humidity conditions. Unfortunately, Mother Nature does not usually give us these ideal conditions, so that limits the value of EER.

SEER. The Seasonal Energy Efficiency Ratio (SEER) tries to overcome some of the shortcomings of the EER. Where the EER only looks at how a cooling system will perform over an hour under ideal conditions, the SEER tries to predict how a cooling system will work over the course of a season. Looking at efficiency over a longer period of time sometimes can give a better picture of efficiency. At the same time, efficiency varies with the conditions. SEER also has some significant shortcomings.

EER and SEER don’t tell the whole story

So why use EER or SEER at all? EER and SEER will never tell you how much a particular cooling unit will cost to operate over an hour or a season. Even so, the measurements give you a way to compare one unit to another. The higher the EER or SEER, the more efficient the unit is, and the less it will cost you to operate.

Condensers can become clogged with leaves and other organic growth. Contaminants like stray garbage and dryer lint can also come into play. Sometimes, people do not consider the position of the dryer exhaust when they place their outside cooling unit. Dryer lint is a good insulator, and can really change a system’s cooling efficiency.

As a condenser becomes dirty, it becomes harder for the cooling system to transfer heat from the refrigerant to the outside air. That leaves more heat in the condenser, which makes the system work harder. It draws more energy, runs longer and doesn’t cool as well.

Efficiency is a big component of the overall cost of cooling. Mathematically, efficiency is simple – power out over power in – but in real life, many variables determine how hard a cooling system has to work. You can’t control things like the outside temperature or humidity, but you can control some things – like how clean your cooling system is.

A dirty system loses efficiency quickly. As the system becomes less efficient, the cost to operate it rises. Changing the filters regularly, having your cooling system professionally inspected and cleaned, and performing regular maintenance can help your cooling system operate at its rated efficiency.

If you would like more information about how to improve the efficiency of your cooling system, please contact us at Boston Standard Company at (617) 288-2911. We can help you maintain your cooling system efficiency, and help you take advantage of its peak efficiency.

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