Nothing’s more important to South Florida homeowners than their AC system. Between rising costs of energy and environmental impact, choosing the most efficient system is critical. But how do you wade through the marketing hype and choose the right one? Here are five efficiency ratings explained to help make the right choice.

On the front of every major appliance, you’ll find a bright yellow sticker showing you its fuel efficiency. But the terms are confusing. Here’s a quick breakdown of what they mean.


“SEER” expresses the efficiency of air conditioning units. It stands for “Seasonal Energy Efficiency Ratio” and provides the unit’s cooling efficiency over the cooling season.

SEER is calculated by dividing the output of cooling by the appliance’s energy consumption through the summer. The higher the SEER rating, the better. AC systems with a SEER of 14 or above get the ENERGY STAR seal.


The EER rating ranges from 11 to 14 and measures real-time efficiency. The EER measures the highest cooling demand by the amount of energy used. “Highest cooling demand” assumes an outdoor temperature of 95 degrees Fahrenheit, an indoor temperature of 85 degrees Fahrenheit, and a relative humidity of 50 percent.


For those with a long-term view of energy efficiency, the IEER measures an air conditioner’s efficiency over the course of a year.

This rating measures the unit’s efficiency at several points: 100 percent demand, 75 percent demand, 50 percent, and 25 percent. It calculates how long the unit works at each level and ascribes a value based on those hours. It then produces a rating based on those demands.


Heat pumps are popular in Florida, and there’s a good reason why. They’re efficient for climates where heating demand is minimal. How efficient? Look at the HSPF rating to find out.

HSPF stands for Heating Seasonal Performance Factor with the highest rating at 10. They determine this number by dividing the heat pump’s energy consumption into the heated square footage of the building over the course of the season.


If you’re in the market for a fuel-burning furnace, you’ll want to know its AFUE rating. The Annual Fuel Utilization Efficiency measures the furnace’s heat output against the total fuel consumption.

While most of the fuel is burned to heat your home, some is lost in gases and venting. This rating is expressed as a percentage of how much fuel is converted to usable heat. The higher the percentage, the better the rating

Invest in Efficiency

While a new HVAC system is a large investment, understanding the efficiency ratings as explained makes it clear that it pays off in the long run. Along with increasing the value of your home, a more efficient system saves you thousands on your utility bills.

Make an appointment today with the experts at One Hour Air in Miami for an estimate on your new system. We’ll show you the new options available for increased savings and long-term value.