Common Home HVAC terms for homeowners to be familiar with: Prep for Bids & Estimates

Home Air Conditioning Basic Terms for homeowners to be familiar with.

When working with heating and air conditioning technicians, sales people and repair services you could hear terms you may not be familiar with. I’ve put together a short list of air conditioning terms you should know before making decisions on what to do when your unit’s  not working properly. This is not a complete list or does it consider all types of heating and air conditioning systems. I work out of College Station, Texas and these systems relate more to our geographical area.

What does HVAC mean?

HVAC stands for Heating, Ventilation and Air Conditioning.

What does SEER mean?

Seasonal Energy Efficiency Ratio. 

The SEER rating of a unit is the cooling output during the cooling season divided by the electrical input during the same season. 

The higher the SEER rating the more energy efficient the unit is.

In 2006 the United States required that residential systems be rated at least 13. Window units were exempt and are typically rated at 10. 

In 2015 Split system central air conditioners are required rating of a minimum of 14 SEER in the Southwestern United States.

These states include, Alabama, Arkansas, Delaware, Florida, Georgia, Hawaii, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Maryland, Oklahoma, South Carolina, Tennessee, Texas and Virginia. The South West region was also included which is Arizona, California, Nevada and New Mexico.

What is the highest SEER rating?

In 2014 Mitsubishi introduced a mini split system rated at 30.5 SEER, additionally there are ground source residential systems with a rating up to 75 SEER.

What does BTU mean?

British Thermal Unit is a traditional unit of heat. It is the amount of heat to raise the temperature of one pound of water by one degree. 

What does a “Ton” mean in cooling?

Defined as the rate of heat transfer that results in the melting of 2,000 pounds ice in 24 hours.

In refrigeration a ton is equivalent to 12,000 BTU/H

What does kilowatt (KW) mean?

A kilowatt is equal to 1,000 watts. The Kilowatt hour is commonly used as a billing unit for energy delivered to consumers by electric utilities.

What does Energy Star mean?

  • Energy Star is a service mark awarded to certified energy efficient products, homes, commercial buildings and industrial plants.

  • Energy Star program was developed by the EPA in 1992.

  • What is a split Central Air Conditioning System?

Central air conditioning allows the interior of a building to be climate controlled using a system of ducts, plenums, fans, filters, blowers, heat exchanger, evaporator and condensing unit to move air through a heated exchanger or a cooled coil. Forced air is blown across the heated or cooled source and distributed through the structure.

What is a Mini Split Ductless System?

A mini-split system supplies air conditioned and heated air to a single room or multi zone systems allow up to 8 rooms to be conditioned by a single exterior unit. The advantage is each room can control temperature separately. 

What is Freon?

Freon is a registered trademark of the Chemours Company, which uses it for halocarbon products. They are stable, nonflammable, moderately toxic gases or liquids which have been used as refrigerants and as aerosol propellants. These include chlorofluorocarbons that cause ozone depletion. New refrigerants do not contain chlorine but use fluorine that is less reactive with the ozone. The term Freon is a common description or proprietary name of refrigerants as with “Coke”, or “Kleenex”.

What is 410-A?

410-a is a refrigerant which contains fluorine that does not contribute to ozone depletion. It is manufactured under the names, Suva 410A, Forane 410A, Puron, EcoFluor 410A, Genetron 410A and AZ-20. As ozone depleting refrigerants are being phased out 410-a is becoming more widely used as a refrigerant.

What is a condenser?

The exterior part of your heating and cooling system. The condenser removes the heat from the system while in the cooling cycle. Condensers are heat exchangers, and can transfer heat to air.

What is a coil?

A coil is equipment that performs heat transfer to air when mounted inside an air handling unit. It is heated or cooled by electrical means or circulating liquid or steam within it.

What is a Damper?

A damper is a plate or gate placed in a duct to control air flow.

What is Delta T?

Delta T is a reference to temperature difference. It is used to describe the difference in temperature of a heating or cooling device as it enters and as it leaves a system.

What is a diffuser?

A diffuser is placed over ductwork. It separates air with vanes going in differing directions and evenly distributes air flow.

What is an evaporator?

The evaporator is a component in the refrigeration cycle that absorbs or adds heat to a system. 

What is a heat exchanger?

The heat exchanger transfers heat from the hot part of a machine or system to the cold parts of the system.

What is a heat pump?

The heat pump is a compressor that cycles hot or cold air. It is designed to move thermal energy in the opposite direction of heat flow by absorbing heat from a cold space and release it to a warmer area.

What is a thermostat?

A thermostat is a device that monitors and regulates a heating and cooling system. It is used to set to a desired temperature and keeps the area warm or cold. It is basically a thermal switch and does not make the area cool or heat faster by setting it to a higher or lower than needed temperature.

What is a zoning System?

A zoning system sections a building into zones which are controlled independently of each other. This helps when different areas of a building have different temperatures, as well as when the desired temperature in separate area is different.

I hope this helped with your repair and understanding of Heating and Air conditioning terminology. There’s lots of great information on the internet. When you’re told about your systems malfunction look it up. You can never have to much information when it comes to the best way spend your hard earned money on home repairs and maintenance.