You might wonder why it’s vital to learn standard HVAC terminology if it’s not your career. However, as a homeowner, you will likely need to hire an HVAC contractor at some point. Even though a good professional will try to explain in simple language, understanding basic terms can help you communicate better with your home heating and cooling technician.
Let’s explore some common HVAC words you need to know.
Air Changes per Hour (ACH)
This phrase refers to how many times the entire volume of air in a given space is replaced with fresh outdoor air within one hour. In an average home, the ACH usually ranges from 0.5 to 1.0, which means the air is completely exchanged approximately every 1 to 2 hours.
American Fuel Utilization Efficiency (AFUE)
It is used to assess a furnace’s efficiency. AFUE involves a mathematical formula that evaluates the ratio of heating output to input.
Balance Point
This term refers to the outdoor temperature, typically between 30° F and 45° F, at which the heating output of a heat pump perfectly matches a home’s heating demands. When temperatures fall below this threshold, supplementary electric resistance heating is required to maintain indoor comfort.
British Thermal Unit (BTU)
It is a measurement of heat defined as the amount of energy required to raise the temperature of one pound of water by one degree Fahrenheit. In the context of cooling systems, a higher BTU rating indicates a greater cooling capacity.
Compressor
This key component in an HVAC system raises the pressure of the refrigerant gas. The compressor allows for more efficient heat absorption and release during the refrigeration cycle.
Condensing/Outdoor Unit
This part of the central air conditioning system is situated outside the house. Its primary role is to act as an exchange point, absorbing heat from the indoor air and releasing it into the outside environment.
Damper
It is a movable plate or valve that manages airflow in an HVAC system. A damper can direct air to particular rooms, control the volume of airflow, or stop back drafting.
Degree Day
It is a measurement obtained by subtracting the average outdoor temperature of a specific area from 65 degrees Fahrenheit. This calculation helps to assess the heating or cooling requirements necessary to maintain a comfortable environment in a building.
Evaporator Coil
This component is part of the heat pump or central air conditioning system found inside the home. It serves as the key point for transferring heat, either warming or cooling the air.
Expansion Valve
It is situated between the liquid and evaporator sections and controls the refrigerant flow into the evaporator coil. The expansion valve creates a pressure drop, enabling the refrigerant to expand quickly, cool off, and absorb heat from the indoor air.
Filter
This detachable part of the furnace is designed to capture airborne particles from the circulating air. The filter prevents them from entering the furnace’s internal components.
Fresh Air Intake
This term refers to a passage that allows outdoor air to flow into your home’s ventilation system. It plays a critical role in ensuring good indoor air quality by replacing stale air with fresh air.
Latent Heat
It is the energy that is either released or absorbed by a substance during a process that occurs at a constant temperature, leading to a change in its state. A typical example is the latent heat of evaporation, which facilitates the transition of a substance from liquid to vapor at a specific pressure and temperature.
Load Calculation
Performed by an HVAC expert, load calculation is vital for determining the appropriate size of a home’s heating or cooling system. This calculation is based on the amount of heat that is either gained or lost.
Manufacturer Approved System
This phrase refers to equipment that a producer has endorsed. When replacing a condensing unit or furnace, the new system must be approved by the manufacturer and meet the Air Conditioning, Heating, and Refrigeration Institute (AHRI) matching standards.
Minimum Efficiency Reporting Value (MERV)
It assesses the performance of air filters used in HVAC systems. The MERV rating signifies the filter’s ability to capture and retain various airborne particles, including dust, pollen, and mold spores. They range from 1 to 16, with higher values indicating a greater capacity to filter out smaller particles effectively.
Reciprocating Compressor
This type of compressor is employed in cooling systems. It compresses refrigerant through the action of a piston.
Refrigerant
It is a specialized chemical substance that facilitates the absorption and release of heat by transitioning between liquid and gas states. This process is fundamental to the operation of refrigeration systems and heat pumps.
Seasonal Energy Efficiency Ratio (SEER)
This metric evaluates the efficiency of an air conditioner in cooling mode. It shows the amount of cooling output the equipment provides for each unit of electricity it uses during the cooling season. A higher SEER rating denotes a more efficient AC.
Split System
It is a type of heating and cooling equipment that has components situated both inside and outside the house. Split system is the most widely used design for residential applications.
Conclusion
Understanding these essential HVAC terms equips you with the knowledge needed to effectively speak with professionals and make informed decisions regarding your home heating and cooling systems. Whether you need a new installation, routine maintenance, or repairs, having a grasp of these concepts can enhance your experience and ensure your house remains comfortable year-round.
Contact a qualified HVAC contractor today to discuss your requirements. They can provide you with tailored solutions and help maintain a cozy and efficient environment in your home.
