HVAC Terminology

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HVAC Terminology


Part of what makes Stellar Air the premier heating and air conditioning contractor serving Garland, TX, and the surrounding areas is our commitment to complete client care and satisfaction. This includes efforts to educate homeowners on some of the common terminology associated with HVAC systems. Here is your guide to the terminology that we use:

Air Quality/Air Deliver Terms

Dehumidifier: A device or system that removes excess moisture from indoor air.

Diffuser: A grille that delivers air throughout your home in a certain pattern over an air supply duct.

Ductwork: A series of pipes that take heated or cooled air throughout your home.

HEPA filter: A specially designed filter that can trap very small particles better than what's possible with a standard filter.

Humidifier: A device or system that adds more moisture to air during the cooler, drier months of the year.

Humidistat: A part that turns a humidifier on and off to control humidity levels.

Capacity/Sizing Terms

British Thermal Unit (BTU): A measure of the heat content of various fuels and/or energy sources. It determines how much cooling power a system offers. BTU can also be referred to as HVAC capacity.

Cubic feet per minute: A reference to airflow volume.

Heat gain/loss: Heat gained or lost within a certain indoor area.

Heat transfer: The movement of air from one space to another.

Heating Seasonal Performance Factor: A measure of a heat pump's efficiency during a specific season.

Load calculation: A determine of what type of HVAC system is appropriate based on your home's energy requirements.

Latent heat: A reference to the energy absorbed or released by a heating/cooling system.

PSI: Pounds per square inch.

Seasonal Energy Efficiency Ratio (SEER): A figure used to determine an HVAC system's overall efficiency.

Ton A measure of cooling capacity.

Voltage: How much electric current a system draws from a home's electrical system.

Watt: A measure of electrical power output.

Heating System Terms

Balance point: A reference to the point when a heat pump's output balances out with your home's heating requirements.

Burner: The device that produces gas.

Burner orifice: An opening for the fuel the burner "burns" or ignites.

Damper: A plate that opens and adjusts to control airflow.

Downflow furnace: Heated air is blown downwards – tends to work best when placed in an attic.

Flue: The byproducts of combustion are removed through this vent.

Furnace: A gas or electric-fueled heating system that can be a standalone unit or one that works with an AC unit or heat pump.

Heat exchanger: A part that transfers heat to a cold surface.

Heating coil: A part that serves as a heat-generating source.

Heat source: The place where heat gathers during a typical heating cycle.

Ignition: Refers to the point where temperatures get high enough to create a flame and produce heat.

Latent heat: Refers to the release or absorption of energy at a constant temperature.

Modulating heating: Your home's temperature is adjusted to improve fuel efficiency and indoor comfort.

Sensible heat: The removal or addition of heat to a room

Supplementary heat: An additional heat source used when temperatures fall below the balance point.

Cooling System Terms

Charging a system: A term used to refer to the process of adding more coolant or refrigerant to a cooling system.

Compressor: The part that circulates refrigerant and helps it flow by maintaining the optimal pressure.

Condensate: Refers to the condensation that occurs when temps decrease as vapor turns into liquid.

Condenser coil: These tubes allow heat from refrigerant vapor to disparate as it turns into liquid form.

Condenser fan: The fan that removes heat from the refrigerant when air goes over the condenser coil.

Drain pan: The pan that collects water when refrigerant transfers to liquid form as it goes to the drain line.

Evaporator coil: The part of a cooling/comfort system that transfers cool or hot air from the inside of your home.

Indoor coil: A coil that connects to a furnace's air handlers to remove heat and moisture and produce cooler air.

Outdoor coil: As heat is lost, this coil changes refrigerate to a liquid.

Outdoor unit: The part of a central AC unit that transfers heated or cooled air.

Refrigerant: A liquid that allows cooling systems to produce cool or conditioned air.

Reciprocating compressor: A part that compresses the cooling liquid in AC/cooling systems.

Temperature Settings

Control: The place where you regulate your home's temperature based on how your HVAC system operates.

Thermostat: The device that allows you to specifically determine the preferred temperature in your home. Newer thermostats can be programmed to learn your preferences over time.

Variable-speed motor: A motor with a fan that works with your thermostat to change the speed used to deliver heated/cooled air within your home.

General HVAC Terms

Cycling: When an HVAC system turns on or off.

Heat pump: A pump that allows for both heating and cooling, depending on what's preferred at various times of the year.

HVAC: A term meaning heating, ventilation, air conditioning, and cooling – a reference to your home's comfort systems.

Hybrid comfort system: A system that gives you the option to switch between different fuel sources.

Indoor/outdoor system: Refers to parts of an HVAC that are either indoors or outdoors. For instance, the main part of a central AC unit is usually outdoors and a furnace is typically an indoor system.

Matched system: A heating/cooling system where all components have equal capacity and efficiency.

Media: Materials that trap dust, allergens, bacteria, and other contaminants.

Orifice: A term for any opening.

Packaged system: All key components are in one cabinet with systems of this nature.

NATE: A certificate program for HVAC contractors administered by a non-profit certification organization.

Split system: An HVAC system where part of the system is outside of your home and the other part is inside.

Two-stage heating/cooling: Speed is adjusted to boost energy efficiency.

Vacuum: Refers to areas where pressure is below standard pressure.

Wet bulb thermostat: Measures relative humidity.

Zoning: A division of your living spaces based on individual cooling/heating preferences in different areas.

Get the Top-Quality Service You Deserve Today

Family-owned and -operated, Stellar Air is the Garland-based HVAC company you can count on to repair, install, and maintain your various comfort systems in the local area. Our team has over 20 years of experience treating homeowners right with convenient service plans, affordable, transparent pricing, and detailed estimates on new installations. Call us or fill out the online form to schedule an appointment.

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    Treat yourself to fast, reliable service from the premier air conditioning contractor in Garland, TX, and nearby areas. Stellar Air is also the company you can count on for transparent pricing and careful attention to every detail. Contact us today to get a detailed estimate or second opinion on a new installation, or to schedule an appointment.