An expansion valve is a device in an HVAC system that controls the flow of refrigerant into the evaporator coil. It reduces the refrigerant's pressure and temperature, allowing it to expand and change into a cooler, lower-pressure state. This process ensures the evaporator coil can absorb heat efficiently from indoor air. Expansion valves can be...

The Fahrenheit scale is a temperature measurement system where water freezes at 32 degrees and boils at 212 degrees under standard atmospheric pressure. It is denoted by the symbol °F. To convert Fahrenheit to Celsius, subtract 32 from the Fahrenheit value, multiply the result by 5, and then divide by 9. For example, to convert...

A mechanical device that creates a flow of air by using rotating blades or impellers, typically powered by an electric motor. In HVAC systems, fans are used to move air through ducts, across coils, or into spaces for heating, cooling, or ventilation purposes. Fans help distribute air effectively to maintain comfort and proper air circulation...

A fan coil unit (FCU) is a simple device used in HVAC systems that includes a heating or cooling coil and a fan. It is typically installed in individual rooms or zones and is used to control the temperature in that specific space. The fan draws air from the room across the coil, which either...

A device used in HVAC systems to trap and remove impurities like dust, pollen, mold spores, and other airborne particles from the air. Filters are crucial for maintaining indoor air quality, protecting HVAC equipment from dirt buildup, and ensuring efficient system operation. They are typically made of materials like fiberglass, pleated paper, or washable mesh...

A type of flexible ductwork used in HVAC systems, typically made from a plastic inner liner surrounded by insulation and a protective outer layer. It is designed to be lightweight, bendable, and easy to install in areas where rigid ductwork would be challenging to fit, such as tight corners, narrow spaces, or irregularly shaped layouts....

A float switch is a safety device used in HVAC systems, usually installed in the drain pan of an air conditioning or heat pump system. Its purpose is to detect when the water level in the drain pan rises too high, which could indicate a clog or other drainage problem. If the water reaches a...

A flue is a duct, pipe, or passageway designed to carry exhaust gases, such as those produced during combustion in a furnace, boiler, or water heater, safely out of a building. It directs these gases, including carbon monoxide, out through a chimney or vent to the atmosphere, ensuring they do not accumulate indoors and pose...

A furnace is a key part of a heating system that generates heat for a building. It works by burning a fuel source, such as natural gas, propane, oil, or using electricity, to produce heat. This heat is then transferred to air (or sometimes water) and distributed throughout the building using ducts (or pipes, in...

A fuse is a safety device used in electrical circuits. It consists of a small metal strip or wire that melts when too much electrical current flows through it. This "breaking" of the circuit prevents damage to more expensive electrical components and reduces the risk of fires or other hazards. Fuses are essential for protecting...