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Elite Air & Heat Dictionary - Your Go-To Guide for All Things HVAC!

Our dictionary is filled with accurate, up-to-date information about HVAC systems, parts, and terminology. From the basics of air conditioning to the inner workings of a furnace, we've got you covered. By giving you the tools and information you need to make informed decisions about your HVAC system, we hope to help you improve your energy-saving efforts and stay comfortable year round. Whether you've been with us for years or are new to Elite Air & Heat, we're excited to share this handy guide with you. It's here to make things easy to understand and full of useful info.

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    1. Airflow Calibration: A service in the realm of air quality that measures and adjusts the volume of air moving through an HVAC system to ensure optimal performance and indoor comfort.
    2. Air Handlers: A device used to regulate and circulate air as part of the heating, cooling, and air quality system.
    3. Air Quality Assessment: A service that measures and analyzes the levels of pollutants and particulates in the indoor environment to determine the need for improvements or interventions.
    4. Airborne Contaminants: Unwanted particles or gases present in the indoor environment, which can affect air quality and necessitate heating or cooling adjustments.
    5. Automatic Thermostat: A device that automatically adjusts the heating or cooling of a space based on pre-set temperature preferences, improving air quality and comfort.
    6. Air Pressure Balancing: A service that ensures even distribution of cooled or heated air throughout a space, enhancing both comfort and air quality.
    7. Air Filter Replacement: A crucial service in maintaining air quality, it involves the changing of filters that trap airborne contaminants.
    8. Air Duct Cleaning: A service essential for good air quality, ensuring that the passages through which air travels are free of dust, mold, and other contaminants.
    1. BTU (British Thermal Unit): A measure of the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. Used to gauge the capacity of heating and cooling equipment.
    2. Blower Motor: The component in an HVAC system that drives air through the ductwork, impacting both heating and air quality.
    3. Bypass Dampers: Devices that allow air to bypass around a zone, thus balancing heating and cooling loads and ensuring optimal air quality.
    4. Boiler Systems: Heating equipment that uses water or steam to distribute heat throughout a space or building.
    5. Biannual Maintenance: A service provided twice a year to ensure the efficient functioning of heating and cooling systems and maintain indoor air quality.
    6. Building Envelope: The physical barrier between the conditioned and unconditioned environment, playing a crucial role in heating, cooling, and air quality.
    7. Blower Door Test: A diagnostic tool used to measure the airtightness of buildings, impacting heating, cooling, and air quality.
    8. Backup Heating Systems: Secondary heating equipment deployed when primary systems fail or require assistance, ensuring uninterrupted comfort.
    1. Compressor: The primary component of cooling systems, responsible for pressurizing the refrigerant and enabling the cooling cycle.
    2. Condenser Coil: A component in cooling systems that releases accumulated heat from the refrigerant to the outside environment.
    3. Carbon Monoxide Detection: A crucial service in the realm of air quality, identifying the presence of this odorless, deadly gas and ensuring safety.
    4. Cooling Load Calculation: A service that determines the amount of cooling required for a space, ensuring optimal comfort and energy efficiency.
    5. Clean Air Delivery Rate (CADR): A measure of an air purifier’s efficiency in terms of cubic feet per minute, essential for understanding and improving air quality.
    6. Central Air Conditioning: A cooling system that provides temperature control and improved air quality to multiple rooms or an entire building from a central location.
    7. Coolant Recharge: A service that replenishes the refrigerant in cooling systems, ensuring optimal performance and energy efficiency.
    8. Calibration of Controls: A service that ensures heating and cooling system controls function accurately, maintaining desired temperature levels and air quality.
    1. Ductwork: A series of channels used to distribute heated or cooled air from the HVAC system throughout a building, playing a pivotal role in both heating and cooling.
    2. Dehumidifier: A device used to remove excess moisture from indoor air, enhancing cooling efficiency and air quality.
    3. Differential Pressure: The variance in air pressure between two points, crucial for the efficient functioning of heating and cooling systems.
    4. Damper: A valve or plate that regulates the flow of air inside the ducts, directly influencing heating, cooling, and air quality.
    5. Dual Fuel Systems: A heating system that combines both gas and electric sources, optimizing efficiency and maintaining consistent indoor temperatures.
    6. Duct Sealing: A service that ensures the air-tightness of ductwork, preventing losses and enhancing heating, cooling, and air quality.
    7. Direct Expansion (DX): A method of cooling where the refrigerant directly cools the air, commonly found in air conditioning systems.
    8. Draft: The movement of air from an area of high pressure to an area of low pressure, impacting heating, cooling, and air quality.
    1. Evaporator Coil: Found inside the air handler, this coil is responsible for absorbing heat from indoor air, playing a key role in cooling.
    2. Energy Recovery Ventilator (ERV): A device that exchanges stale indoor air with fresh outdoor air without significant energy loss, benefiting both cooling and air quality.
    3. Electronic Air Cleaner: An air purification system that uses electrical charges to trap and eliminate airborne contaminants, enhancing air quality.
    4. Efficiency Rating: A metric indicating how effectively a heating or cooling unit operates in comparison to the energy it consumes.
    5. Expansion Valve: A device in cooling systems that controls the amount of refrigerant flow to the evaporator coil.
    6. Economizer: A device or system designed to reduce energy consumption, especially in heating and cooling applications.
    7. Exhaust Ventilation: Systems designed to remove stale indoor air, promoting better air quality.
    8. Environmental Controls: Systems and devices used to manage and maintain indoor air quality, temperature, and humidity levels.
    1. Forced Air System: A heating or cooling system that uses air as its medium, distributing it via ductwork throughout a space.
    2. Filter Replacement Schedule: A recommended timeline for changing air filters to ensure optimal air quality and system efficiency.
    3. Fan Coil Unit: A simple device consisting of a heating or cooling coil and a fan, used to control the temperature in the space where it’s installed.
    4. Freon: A brand of refrigerant used in cooling systems; its presence and levels are crucial for optimal cooling performance.
    5. Furnace: A device designed for high-temperature heating, playing a key role in many residential and commercial heating systems.
    6. Flow Rate: The volume of air that moves through a specific point in the HVAC system in a given amount of time, influencing both heating and cooling.
    7. Fresh Air Intake: A component in ventilation systems that allows outdoor air to enter the HVAC system, impacting air quality.
    8. Fan Limit Switch: A safety device on furnaces that turns the fan on and off based on temperature, ensuring safe heating operations.
    1. Geothermal Heat Pump: A heating and cooling system that transfers heat between the ground and a building, known for its energy efficiency.
    2. Grille: An opening with a cover in floors, walls, or ceilings that facilitates the passage of air for heating, cooling, and ventilation.
    3. Gas Furnace: A type of furnace that uses natural gas as its fuel source, commonly employed in residential heating.
    4. Glycol System: A system that uses glycol (usually mixed with water) to transfer heat, commonly found in commercial HVAC applications.
    5. Gravitational Ventilation: A natural ventilation method where hot air rises and escapes from upper openings, pulling cooler air in from below.
    6. Guarded Test: A test in which surrounding conditions are controlled to ensure accurate results, often used in assessing HVAC system efficiency.
    7. Green Building: A building designed with energy efficiency and environmental sustainability in mind, including optimized heating, cooling, and air quality systems.
    8. Gas Valve: A device in a furnace that regulates the flow of gas to the burners, playing a crucial role in heating.
    1. Heat Exchanger: A device that transfers heat from one medium to another, fundamental to many heating systems.
    2. Humidifier: A device that adds moisture to indoor air, often used alongside heating systems to improve comfort and air quality.
    3. Heat Pump: A device that transfers heat from a colder area to a warmer area, used for both heating and cooling purposes.
    4. Heating Load Calculation: A service determining the amount of heat required to warm a space adequately.
    5. Hydronic Systems: Heating or cooling systems that use water or another liquid as a heat-transfer medium.
    6. HVAC Zoning: The practice of dividing a space into zones and independently controlling the temperature and air quality in each.
    7. High-Efficiency Particulate Air (HEPA) Filter: A type of air filter that can trap a large percentage of particles, beneficial for optimal air quality.
    8. Heat Recovery Ventilator (HRV): A device that exchanges stale indoor air with fresh outdoor air, recovering heat in the process.
    1. Indoor Air Quality (IAQ): A measure of the cleanliness and healthiness of air within and around buildings and structures.
    2. Infiltration: The unintentional or accidental introduction of outside air into a building, typically through gaps, cracks, or openings.
    3. Insulation: Materials used to prevent the loss or gain of heat, playing a crucial role in both heating and cooling applications.
    4. Intake Vent: An opening or duct that draws in outside air, used in various heating, cooling, and ventilation systems.
    5. Integrated Systems: HVAC systems that combine multiple functions, such as heating, cooling, and air purification, into a single unit.
    6. Ionizer: A device that uses ions to purify air, removing contaminants and improving air quality.
    7. Induction Units: Devices that use primary air to induce room air through the heat exchanger, employed in some HVAC systems.
    8. Intelligent Controls: Advanced system controls that use algorithms and data analysis to optimize HVAC operations for efficiency and comfort.
    1. Joule: A unit of energy equivalent to one watt-second, often used in the context of heating and cooling calculations.
    2. Jet Diffuser: A device used in HVAC systems to direct air in a specific direction or pattern.
    3. Joint Compound: A material used to seal joints in HVAC systems, preventing leaks and enhancing efficiency.
    4. Junction Box: An enclosure within HVAC systems where wiring connections are made.
    5. Jacket: An outer covering or insulation layer on boilers or other HVAC equipment to reduce heat loss.
    6. Jumper: A temporary connection in HVAC electrical circuits, used during testing or maintenance.
    7. Jack Shaft: A shaft that connects a motor to the equipment it drives in some HVAC applications.
    8. Just-In-Time Service: A service strategy that aims to provide timely maintenance and repairs, ensuring minimal downtime and disruptions in heating, cooling, and air quality systems.
    1. Kilowatt (kW): A unit of power equivalent to one thousand watts, commonly used to measure the capacity of heating and cooling equipment.
    2. Kilowatt-Hour (kWh): A unit of energy used to represent the amount of electricity consumed by HVAC equipment over a specific period.
    3. Kinetic Energy: Energy possessed by a body due to its motion, often considered in HVAC systems in relation to airflow and fluid movement.
    4. K-Factor: A measure of the thermal conductivity of a material, indicating its ability to conduct heat, crucial in insulating and building materials affecting heating and cooling.
    5. Knockout Plug: A removable plug in HVAC equipment that allows for the insertion of conduits or pipes.
    6. Kick Space Heater: A compact heating device installed in spaces like under cabinets, delivering localized heating.
    7. Keyed Damper: A damper in HVAC ductwork that can be adjusted with a specific key, offering precise control over airflow.
    8. Kink: A sharp bend or twist in pipes or ducts that can obstruct the flow, impacting heating, cooling, and air quality.
    1. Load Calculation: A detailed analysis to determine the heating or cooling requirements of a building, ensuring optimal equipment sizing.
    2. Latent Heat: The heat energy absorbed or released during a change in state (e.g., liquid to gas) without a change in temperature.
    3. Linear Diffuser: An elongated grille designed to distribute air across a wide area, commonly used in commercial HVAC installations.
    4. Louvers: Slatted devices installed in a duct or opening to allow airflow while blocking unwanted elements like debris.
    5. Low-E (Low Emissivity): A type of window glass coated to minimize the amount of infrared and ultraviolet light that passes through, aiding in efficient heating and cooling.
    6. Leak Detection: A service to identify and locate refrigerant or fluid leaks in HVAC systems, ensuring efficient operation.
    7. Low-Pressure System: An HVAC system or component that operates at pressures lower than atmospheric pressure, often used in specific cooling applications.
    8. Load Factor: The ratio of the actual load over a period to the maximum possible load over the same period, indicating HVAC system efficiency and utilization.
    1. Mechanical Ventilation: Ventilation systems powered by machinery, such as fans or blowers, to maintain air quality.
    2. Modulating Furnace: A furnace that adjusts its heating output based on demand, ensuring consistent indoor temperatures and increased efficiency.
    3. Manual J: A widely accepted method for heat load calculation, ensuring the correct sizing of HVAC equipment.
    4. MERV Rating (Minimum Efficiency Reporting Value): A standard rating that measures the efficiency of air filters in trapping airborne particles, crucial for air quality.
    5. Mixing Box: A component in HVAC systems where fresh air and return air are mixed before entering the heating or cooling equipment.
    6. Make-Up Air Unit (MAU): An HVAC device that brings in fresh, outdoor air to replace exhaust air, aiding in maintaining indoor air quality.
    7. Modulating Valve: A valve that can be adjusted to varying positions to control the flow of fluid, used in some heating and cooling systems.
    8. Manifold: A pipe or chamber branching into several openings, commonly used in HVAC systems to distribute or collect gases or liquids.
    1. Natural Ventilation: The process of supplying and removing air in an indoor space without the use of fans or mechanical systems, relying on natural forces like wind.
    2. Negative Air Pressure: A condition where the air pressure inside a space is lower than outside, leading to potential air quality issues.
    3. Nominal Capacity: The rated or designated capacity of HVAC equipment, usually under standardized test conditions.
    4. Noise Dampening: Techniques or materials used to reduce sound produced by HVAC equipment, enhancing user comfort.
    5. Nest Thermostat: A brand of smart thermostats that learn user preferences over time, optimizing heating and cooling for comfort and efficiency.
    6. Non-Condensable Gas: A gas that doesn’t condense into a liquid at typical operating pressures and temperatures, potentially affecting cooling system performance.
    7. NEMA Ratings: Standards set by the National Electrical Manufacturers Association, indicating the type of environment in which an electrical enclosure can be used.
    8. Neutral Air: Air that is neither supplied nor exhausted, typically referring to air that remains relatively motionless in a space.
    1. Outdoor Air Intake: The part of an HVAC system that draws in exterior air, a critical component for ventilation and air quality.
    2. Oversizing: The practice of installing HVAC equipment with a higher capacity than necessary for the given space, which can lead to inefficiency and reduced equipment lifespan.
    3. Operating Cost: The total expense associated with running HVAC equipment, including energy bills, maintenance, and repairs.
    4. Orifice: A small hole or opening in an HVAC component, typically used to control the flow of fluid or air.
    5. Occupancy Sensors: Devices that detect the presence of people in a space and adjust heating, cooling, or ventilation accordingly, enhancing efficiency.
    6. Off-Peak Cooling: Cooling strategies or systems that operate primarily during periods of lower energy demand or cost.
    7. Ozone-Friendly: Refers to substances or practices that do not harm the ozone layer, especially relevant to certain refrigerants in cooling systems.
    8. Open Loop System: In HVAC, a system that draws water or another medium from an external source, uses it for heating or cooling, and then discharges it.
    1. Programmable Thermostat: A device that allows users to set specific temperatures for different times of day or days of the week, improving efficiency in heating and cooling.
    2. Packaged Unit: An all-in-one HVAC system where the compressor, condenser, and evaporator are combined in a single unit, often used in commercial settings.
    3. Pressure Drop: The decrease in pressure as air or fluid moves through an HVAC system or its components, which can affect system efficiency.
    4. Purging: The process of clearing air or other gases from a section of an HVAC system, typically to improve performance or as a safety measure.
    5. Plenum: A space or chamber in which air or another medium is collected before being distributed, often found in ventilation systems.
    6. Particulate Matter: Tiny solid or liquid particles suspended in air, which can be filtered out to improve air quality.
    7. Psychrometric Chart: A graphical representation of the properties of moist air, used by HVAC professionals to determine air conditions and system requirements.
    8. Passive Solar Design: A strategy that utilizes the sun’s energy for natural heating and lighting, reducing the need for mechanical heating systems.
    1. Quality Control: Procedures implemented to ensure the proper design, installation, and operation of HVAC systems.
    2. Quarterly Maintenance: Routine checks and services carried out every three months to ensure optimal HVAC system operation and longevity.
    3. Quick Connect: A type of connection used in HVAC systems for easy and rapid coupling and uncoupling of components.
    4. Quadratic Dampers: Dampers designed to adjust airflow in a system in a quadratic or non-linear relationship to damper position.
    5. Qualitative Assessment: Evaluating the non-numerical aspects of an HVAC system, such as comfort levels or air freshness.
    6. Quantitative Analysis: Numerical evaluation of HVAC system parameters, such as temperature, airflow, or energy consumption.
    7. Q-Factor: In HVAC, a measure of the rate of heat transfer through a material or assembly.
    8. Quenching: Rapidly cooling a substance (like hot metal or gas) by immersing it in a liquid or by blowing a cooler medium over it.
    1. Quality Control: Procedures implemented to ensure the proper design, installation, and operation of HVAC systems.
    2. Quarterly Maintenance: Routine checks and services carried out every three months to ensure optimal HVAC system operation and longevity.
    3. Quick Connect: A type of connection used in HVAC systems for easy and rapid coupling and uncoupling of components.
    4. Quadratic Dampers: Dampers designed to adjust airflow in a system in a quadratic or non-linear relationship to damper position.
    5. Qualitative Assessment: Evaluating the non-numerical aspects of an HVAC system, such as comfort levels or air freshness.
    6. Quantitative Analysis: Numerical evaluation of HVAC system parameters, such as temperature, airflow, or energy consumption.
    7. Q-Factor: In HVAC, a measure of the rate of heat transfer through a material or assembly.
    8. Quenching: Rapidly cooling a substance (like hot metal or gas) by immersing it in a liquid or by blowing a cooler medium over it.
    1. SEER (Seasonal Energy Efficiency Ratio): A measure of the efficiency of an air conditioner or heat pump, indicating the cooling output divided by the energy consumed over a season.
    2. Split System: A type of HVAC system where components are divided into indoor and outdoor units, typically including an indoor evaporator and an outdoor condenser.
    3. Supply Air: The conditioned air that is delivered by an HVAC system into a space.
    4. Static Pressure: The pressure exerted by air at rest in an HVAC system, crucial for ensuring proper airflow and system efficiency.
    5. Subcooling: The process of reducing the temperature of liquid refrigerant below its condensation point, enhancing the efficiency of cooling systems.
    6. Superheat: The amount by which the temperature of a vapor exceeds its vaporization point at a given pressure, crucial in refrigeration systems.
    7. Setback Thermostat: A thermostat that can lower or raise the temperature during periods of reduced activity, such as nighttime, to save energy.
    8. Supply Duct: The ductwork that distributes conditioned air from HVAC equipment to the occupied spaces.
    1. Thermostat: A device that monitors and controls the temperature in a space by activating heating or cooling systems.
    2. Ton: A unit of measurement for cooling capacity, with one ton equivalent to the amount of heat required to melt a ton of ice in 24 hours (approximately 12,000 BTU/hour).
    3. Total Heat Load: The sum of all heat sources in a space, including occupants, equipment, and sunlight, which determines the cooling requirement.
    4. Two-Stage Cooling: An HVAC system that can operate at two levels of cooling output, optimizing energy use and comfort.
    5. Thermal Envelope: The boundary in a building that separates conditioned spaces from unconditioned spaces, impacting energy efficiency.
    6. Terminal Unit: An individual device, like a radiator or coil, that transfers heat between the HVAC system and the occupied space.
    7. Turndown Ratio: The ratio of a system’s maximum capacity to its lowest sustainable output, indicating its operating range.
    8. Transmittance: The rate at which heat or light passes through a material, affecting heating and cooling needs.
    1. U-Factor (Thermal Transmittance): A measure of how effectively a building material conducts heat, with lower values indicating better insulating properties.
    2. Ultraviolet (UV) Lights: Used in HVAC systems to kill bacteria and mold, improving air quality.
    3. Unconditioned Space: An area or room within a building not serviced by the HVAC system, typically attics or garages.
    4. Underfloor Heating: A system where heating elements are placed beneath the floor, radiating heat upwards to warm a space.
    5. Unit Heater: A standalone heating device designed to heat a specific area or room.
    6. Upflow Furnace: A type of furnace that draws in cool air from the bottom and releases heated air from the top.
    7. User Interface: The controls or panels on HVAC equipment that allow users to adjust settings and monitor performance.
    8. U-tube Heat Exchanger: A specific type of heat exchanger design where tubes are bent in a U-shape, facilitating efficient heat transfer.
    1. Ventilation: The process of supplying fresh air to and removing stale air from an indoor space, either naturally or mechanically, crucial for maintaining good air quality.
    2. Variable Air Volume (VAV): A system that provides flexible airflow rates, adjusting to the specific cooling or heating needs of different areas.
    3. Variable Refrigerant Flow (VRF): An HVAC technology that allows the precise control of refrigerant flow to multiple indoor units, optimizing efficiency.
    4. Vent: An outlet or inlet through which air is moved into or out of a space.
    5. Vapor Barrier: A material used to prevent the passage of water vapor, often installed in walls or ceilings to control moisture levels.
    6. Venturi: A narrowed section in a tube or duct, used in HVAC to measure fluid flow rates or to mix fluids.
    7. Volute: A spiral casing around a fan or pump impeller, guiding the flow of fluid.
    8. Variable Speed Motor: A motor that can operate at a range of speeds, allowing for more precise control of HVAC equipment performance.

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    1. Whole-House Fan: A ventilation system that moves air throughout an entire house, typically used to replace stale indoor air with fresh outdoor air.
    2. Wet-Bulb Temperature: The lowest temperature that can be achieved by evaporating water into the air, important in psychrometrics and HVAC calculations.
    3. Water Source Heat Pump: An HVAC system that uses water as a heat exchange medium, either extracting heat from or dissipating heat to the water.
    4. Watt (W): A unit of power, commonly used to measure the energy consumption of HVAC equipment.
    5. Weatherstripping: Material used to seal gaps around windows and doors, preventing drafts and enhancing energy efficiency.
    6. Window Air Conditioner: A compact air conditioning unit designed to fit in a window frame, cooling a single room or area.
    7. Wing Nut: A type of nut with two wings, allowing for hand tightening, often used in HVAC components for easy adjustments or installations.
    8. Winterization: Preparing an HVAC system or building for cold weather to ensure efficient heating and prevent damage.
    1. X-Flow Heat Exchanger: A type of heat exchanger where fluids flow perpendicular to one another, enhancing heat transfer rates.
    2. X-Factor: A term used in psychrometrics to represent the moisture content of air, impacting both heating and cooling calculations.
    3. X-Section: A view or diagram of an HVAC component or system when cut across a specific plane, providing insight into its internal configuration.
    4. Xenon Lighting: High-intensity lighting systems sometimes used in large HVAC installations or facilities.
    5. Xeriscaping: Landscaping that reduces or eliminates the need for supplemental water, potentially impacting the cooling needs of a building.
    6. X-Damper: A type of damper used in special HVAC applications, often characterized by its specific shape or function.
    7. X-Grid: A support or structure within an HVAC system or component, named for its cross-hatched or X-shaped design.
    8. X-Value: A hypothetical term, often used in advanced HVAC discussions or as a placeholder for specific metrics.
    1. Y-Strainer: A device in HVAC systems that removes unwanted particles from fluids, protecting equipment and ensuring efficient operation.
    2. Y-Terminal: On a thermostat, the terminal that typically controls the cooling system.
    3. Yield Strength: The amount of stress a material can withstand without permanent deformation, relevant to HVAC components and ductwork.
    4. Y-Damper: A type of damper shaped like the letter “Y”, used to split or merge airflow in duct systems.
    5. Yoke: A stabilizing frame or bracket used in some HVAC components or equipment.
    6. Y-Connection: A junction in ductwork or piping that splits a flow into two paths.
    7. Yaw: A rotational movement or alignment adjustment of an HVAC component, especially relevant in fan installations.
    8. Yield Point: The stress level at which a material begins to deform plastically, critical in the design of resilient HVAC systems.
    1. Zone Control: The ability to control heating or cooling in specific areas or rooms of a building independently, optimizing comfort and efficiency.
    2. Zoned System: An HVAC system designed to heat or cool different areas or rooms at different temperatures or conditions.
    3. Zero Energy Building: A building with a net energy consumption of zero, often achieved through a combination of high-efficiency HVAC systems and renewable energy sources.
    4. Zone Damper: A device used in zoned systems to regulate airflow to specific areas or rooms.
    5. Zone Valve: A device in heating systems, particularly in hydronics, that controls the flow of heated water to specific areas or radiators.
    6. Zulu Time: Also known as Coordinated Universal Time (UTC), sometimes referenced in HVAC system scheduling or data logging.
    7. Zeolite: A type of mineral sometimes used in HVAC systems for its moisture-absorbing properties.
    8. Zinc Coating: A protective layer applied to some HVAC components, providing corrosion resistance.
    9.