- This is a percentage measurement of a furnace's heating efficiency. The U.S. government's minimum efficiency
level is 78%. The higher the AFUE, the more efficient the furnace. The
initials stand for Annual Fuel Utilization Efficiency.
- Air Handler
- This is the indoor section of a split system. It can be a dedicated air
handler, or could be your furnace. Also known as a fan-coil.
- Air-Conditioning, Heating and Refrigeration Institute. AHRI is an industry trade association that develops
standards for measuring and certifying product performance. For instance, AHRI Standard 270 provides
guidelines for establishing sound levels for outdoor air-conditioning equipment.
- The distribution or movement of air.
- AMBIENT TEMPERATURE
- This is the air temperature (usually the outdoor air temperature) surrounding the equipment.
- Microscopic living organisms suspended in the air that grow and multiply in warm, humid places.
- British Thermal Unit. This is the amount of heat required to raise the temperature of one pound of water by
one degree Fahrenheit. You'll see this measurement when you look at heating and cooling capacities. For
example, your dealer may recommend a 75,000 Btu furnace and a 24,000
Btu air conditioner for your home.
- Comfort Sync® A3
- Armstrong Air’s most advanced thermostat. Communicates with all the different system components for
increased efficiency and control, plus offers the ability to control the system remotely from anywhere in
- Condensing Unit
- This is the outdoor section of a split-system air conditioning
system. You'll know it best as the air conditioner that sits
outside your home.
- Coefficient Of Performance. A ratio that compares a heat pump system's
heating efficiency to that of electric resistance heat. For example, a heat
pump system with a COP of 3.0 provides heat at 3 times the efficiency of electric resistance heat. A
heat pump's system COP will decrease as outdoor temperatures drop, eventually providing little or no
efficiency advantage over electric resistance heat—and that's when your auxiliary heat strips start to
heat your home.
- Communicating thermostat
- Establishes an electronic connection between all the different heating and cooling system components to
optimize overall performance, efficiency and comfort.
- Dual Fuel
- For even greater efficiency, this heat pump can be paired with a furnace. Called a dual-fuel system, this combination minimizes
heating costs by seamlessly alternating between the two energy sources, depending on outdoor conditions.
- Energy Efficiency Rating.
- ENERGY STAR
- Products/homes/buildings that earn the ENERGY
STAR® qualification prevent greenhouse gas emissions by meeting strict energy
efficiency guidelines set by the U.S. Environmental Protection Agency and the U.S. Department of Energy. To
learn more, please visit www.energystar.gov.
- Gallons Per Hour. You might see this rating if you are looking at an oil
furnace. In addition to input and output, an oil furnace also
has a rating of gallons per hour, the volume of oil a furnace is capable of burning in 60 minutes.
- Heat Pump
- A unit that both cools and heats your home. A heat pump system can be
either a split system or a package system. A heat pump can be used in
conjunction with a gas/oil/LP furnace (using the furnace instead of
electric resistance heat when temperatures fall below about 35° F) with the addition of a fossil fuel kit.
- This is a measurement of a heat pump's heating efficiency. The U.S government’s minimum efficiency level
is 8.2 HSPF (7.5 HSPF2). The higher the HSPF, the more efficient the heat pump's heating performance. HSPF
stands for Heating Seasonal Performance Factor. This rating has been officially replaced by HSPF2.
- In 2023, the Department of Energy implemented new, stricter standards for testing the efficiency of heat
pump products in heating mode. These more accurately reflect a unit’s performance in real life installations.
Like HSPF, the previous rating system, HSPF2 is a measurement of a heat pump's heating efficiency. What’s the
difference? Think of it as highway vs. city miles per gallon. Like highways miles per gallon, HSPF represents
performance in perfect conditions, whereas HSPF2 reflects performance in real-world installations—similar
to stop-and-go traffic in city miles per gallon.
- For heat pump split systems, the U.S government’s minimum efficiency level is 7.5 HSPF2. HSPF stands for
Heating Seasonal Performance Factor. The higher the HSPF, the more efficient the heat pump's heating
- HVAC (pronounced either "H-V-A-C" or "aitch-vak") is an acronym that stands for the closely related
functions of "Heating, Ventilating, and Air Conditioning."
- Mini-Splits System
- Mini-splits are heating and cooling systems that allow the temperature in individual rooms or spaces to be controlled.
Mini-split systems consist of two main components; an outdoor compressor/condenser and an indoor air-handling unit(s).
- Package System
- Package units provide both heating and cooling from one unit that is
placed outside the home—on the ground, on the roof, or sometimes mounted through the walls of the
building. Package units come in several combinations of fuel
sources—gas heat/electric cooling; heat pump; electric
heat/electric cooling; oil heat/electric cooling.
- Remote Access
- Armstrong Air’s Comfort Sync thermostat connects to your home’s Wi-Fi network, allowing you to access and
adjust your heating and cooling system from anywhere in the world using a smartphone or other web-enabled
- This is a measurement of the efficiency of cooling products. The U.S government’s minimum efficiency level
is 14 SEER (13.4 SEER2) in northern states, and 15 SEER (14.3 SEER2) for southern and southeastern states. The
higher the SEER, the more efficient the cooling product. SEER stands for Seasonal Energy Efficiency Rating.
This rating has been officially replaced by SEER2.
- In 2023, the Department of Energy implemented new, stricter standards for testing the efficiency of cooling
products. These more accurately reflect a unit’s performance in real-life installations. What’s the difference?
Think of it as highway vs. city miles per gallon. Like highway miles per gallon, SEER represents performance in
perfect conditions, whereas SEER2 reflects the performance in real-world installations—similar to stop-and-go
traffic in city miles per gallon.
- For split systems, the U.S. government’s minimum efficiency level is 13.4 SEER2 in northern states, and
14.3 SEER2 for southwestern and southeastern states. SEER stands for Seasonal Energy Efficiency Rating.
The higher the SEER2, the more efficient the cooling product.
- Split System
- This describes an air conditioning or heat pump system that is split into two sections—an outdoor
section and an indoor section. It won't work without the outdoor section plus an indoor section to move the
- You'll often see this as a measurement of the capacity of an air
conditioning system. Don't panic, it doesn't measure weight! Just like gas and oil furnaces, air conditioners and heat
pumps are rated in Btus. One ton of air conditioning is
12,000 Btus per hour. This means that a "one ton" air conditioning
system has the capability of removing 12,000 Btus of heat per hour from your home.