Understanding Efficiency Ratings for Heat Pumps and Air Conditioners

Efficiency ratings are like gas mileage – the higher the rating, the more efficient the product is. All products are given the following ratings, so you’ll know exactly what to expect from your investment.

AFUE
(Annual Fuel Utilization Efficiency)
The AFUE is the most widely used measure of a furnace’s heating efficiency. It measures the amount of heat actually delivered to your house compared to the amount of fuel that you must supply to the furnace. Thus, a furnace that has an 80% AFUE rating converts 80% of the fuel that you supply to heat — the other 20% is lost out of the chimney. This measurement gauges heating fuel usage.

Note that the AFUE refers only to the unit’s fuel efficiency, not its electricity usage.

HSPF
(Heating Seasonal Performance Factor)
This measurement gauges the heating mode of heat pumps. Most new units have ratings from 7.0 to 9.4.

Don’t assume the HSPF will be an accurate predictor of your actual installed performance as this rating is based on laboratory testing in ideal/perfect conditions that are unlikely to coincide with your climate. In the lower mainland of British Columbia your actual performance with a well-designed and installed system may actually match or come very close to the HSPF rating. But east of the Rockies (prairie provinces) and north your actual performance may be a bit lower due to colder winter air temperatures.
The Infinity heat pump receives up to 9.5 HSPF.

(Seasonal Energy Efficiency Ratio)
This measurement gauges air conditioning cooling. All new models are required as of January 2006 to have at least a 13.0 SEER rating.

Cooling performance is rated using the SEER (Seasonal Energy Efficiency Ratio). The higher the SEER the more efficiently the heat pump cools. The SEER is the ratio of heat energy removed from the house compared to the energy used to operate the heat pump, including fans.

Ton
It can get a little confusing talking about the heating or cooling capacity of a heat pump. A common sizing measurement is the “ton.” This is a holdover from the days when refrigeration was used mostly to make ice (to sell to people who had ice boxes). A “three ton” refrigeration unit could make three tons of ice from 32 degrees F water in a day.

We know you’re not making ice, but people still talk about heat pumps in tons. One ton is roughly equivalent to 12,000 Btu per hour heat output when the air is 47 degrees F outdoors, or 12,000 Btu cooling at 95 degrees F.

So what’s a Btu? This is the most common measure of heat energy in the American heating and cooling industry. It stands for British Thermal Unit and is a small amount of energy, roughly equivalent to the energy given off from burning a wooden match.

Refrigerants
Freon®–22 Refrigerant Since its debut in 1930, Freon refrigerant has been used in cooling systems. And while it’s still available, the Clean Air Act of 1990 prohibits the production of Freon–22-based air conditioners and heat pumps by 2010, and Freon–22 production by 2020. As Freon–22 production declines, its cost is predicted to rise. (Freon is a registered trademark of E.I. duPont de Nemours & Company.)

Puron® Refrigerant (R410A)
Carrier was the first to introduce a new, non-ozone-depleting refrigerant called Puron – a full six years ahead of the competition — paving the way for the future. Puron refrigerant is chlorine-free, so it doesn’t damage the Earth’s ozone layer. And, as other refrigerants become less available, Puron refrigerant will be the refrigerant of choice for years to come