HVAC Glossary
A
Our Accessories collection includes everything from mounting brackets to specialized heat kits.
Acoustic dampening architecture involves the internal soundproofing of the indoor and outdoor units to ensure a peaceful living environment.
Acoustic resonant isolation involves using mechanical dampeners to prevent the vibration frequency of the compressor from matching the natural frequency of the house structure.
Active BTU modulation is the system's ability to dynamically scale its cooling or heating output based on the current indoor temperature fluctuations.
Air filtration in a mini-split involves multi-stage filters that remove dust, allergens, and odors from the indoor air.
The air handler is the indoor portion of a mini-split system that circulates and filters the air within the room.
Ambient cooling optimization is the system's ability to maintain high SEER efficiency even when outdoor temperatures are extreme.
Anti-cold draft protection prevents the indoor fan from turning on in heat mode until the coil is warm enough to provide hot air.
Every Bravo Milano condenser cabinet is treated with a multi-stage anti-corrosive powder coating to withstand the harshest outdoor elements.
Auto restart is a feature that turns the mini-split back on with its previous settings after a power outage.
The auto-restart function ensures that if a power outage occurs, the system will automatically return to its previous settings once power is restored.
B
A BTU is a traditional unit of heat defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.
BTU calibration is the process of matching the cooling or heating capacity of a unit to the specific square footage and insulation of a room.
Load shifting is a smart feature of our multi-zone condensers that allows extra power to be diverted to a single room if others are not in use.
BTU tiering is a product strategy that offers different cooling power levels within the same model family to suit diverse room sizes.
Evaporator matching is the engineering requirement that the indoor head's capacity exactly matches the signal sent from the outdoor condenser.
The Bravo Milano 9,000 BTU Universal Floor Ceiling is our most compact UFC unit.
C
Capillary flow synchronization is the method used in smaller units to ensure the refrigerant pressure is dropped precisely before entering the cooling coil.
A cased A-coil is an evaporator coil housed in a metal cabinet, typically used with a furnace or air handler.
A ceiling cassette is an indoor air handler that is recessed into the ceiling, showing only a decorative grille.
Centrifugal condensate evacuation is an advanced method of removing moisture using a high-RPM internal pump designed for high-lift scenarios.
Coil maximization refers to the use of inner-grooved copper and high-density aluminum fins to increase the area available for heat transfer.
Compact footprint engineering is the design philosophy of making outdoor condensers as small as possible without sacrificing cooling capacity.
Oil management is the process of ensuring that the lubricant for the compressor is periodically returned to the outdoor unit from the long copper lines.
Slim duct integration refers to the ability to hide the indoor unit within a ceiling plenum or crawlspace, leaving only subtle registers visible in the room.
The condensate drain hose carries the water removed from the air to the outside.
Lift-pump integration involves a built-in mechanical pump that can push drainage water vertically, allowing for flexible indoor unit placement.
Gravity-drain optimization is the internal design of the drain pan that ensures every drop of water flows out without pooling, even if the unit is slightly off-level.
Elevation strategy involves the strategic placement of the outdoor unit to protect it from flooding, snow, or debris.
The condensing unit is the outdoor part of the mini-split system that houses the compressor and condensing coil.
The Cooper & Hunter Astoria Series is known for its high-efficiency wall-mounted units.
Line-set integrity refers to the quality and insulation thickness of the copper tubing that connects the indoor and outdoor components.
Cross-flow fans use a long, cylindrical blade design that moves air horizontally across the entire width of the indoor unit.
D
Sine-wave control is the advanced digital processing of the electrical signal to make the motor run as smoothly and efficiently as possible.
Dehumidification mode is a setting on many mini-splits that removes excess moisture from the air without significantly lowering the temperature.
Direct-expansion (DX) inverter cooling is the process where the refrigerant expands directly in the evaporator coil of the indoor unit to absorb heat.
A drain pump is used to move condensation away from the indoor unit when gravity drainage isn't possible.
A Dual Zone setup involves two indoor air handlers powered by one outdoor condenser.
Thermal synchronicity is the ability of two indoor units to communicate through the condenser to maintain a perfectly balanced load across a shared floor plan.
Ductless AC refers to cooling systems that don't use ducts, providing high efficiency and easy installation.
Descaling is the maintenance process of removing mineral or biological buildup from the indoor evaporator fins to maintain airflow.
A ductless heat pump provides both heating and cooling without the need for air ducts.
A ductless system provides heating and cooling directly to a room without the need for complex metal ductwork.
The oil-return cycle is an automated logic routine that ensures the compressor's lubricant is pulled back from the long line sets periodically.
E
The EEV is a motorized valve that replaces old-fashioned fixed orifices to provide precise control over refrigerant flow.
Corrosion protection involves the application of a specialized "Gold Fin" or "Blue Fin" coating to the condenser coils to prevent salt and moisture from eating the metal.
An expansion valve regulates the amount of refrigerant flow into the evaporator coil.
F
A flare nut is used to create a leak-proof connection between the copper line set and the mini-split unit.
Floor-mount trajectory is the specific angle at which a floor-standing unit directs air upward and outward to ensure it doesn't just "pool" on the ground.
Floor-to-ceiling versatility refers to the unique chassis design of certain indoor units that can be installed on either the floor or the ceiling.
Four-way diffusion refers to the ability of an indoor unit to discharge air from all four sides simultaneously to create a balanced temperature.
G
Gold-fin protection is a specialized hydrophilic coating on the outdoor heat exchanger that accelerates defrosting and resists corrosive salts.
A ground stand is a mounting accessory used to elevate the outdoor condenser above the dirt, snow, or water.
H
A heat kit is an auxiliary electric heater installed inside an air handler to provide extra warmth during extreme cold.
A heat pump is a versatile HVAC component that provides both cooling in the summer and heating in the winter by reversing the refrigerant flow.
Our advanced defrost logic uses a reverse-cycle method to melt ice from the outdoor coil in minutes, rather than hours.
High-static pressure handling refers to the ability of an indoor unit to push conditioned air through longer or more complex duct runs without losing velocity.
High-torque DC motors are used in our blower units to provide powerful airflow while consuming a fraction of the power used by traditional AC motors.
Redistribution is a feature of our larger condensers that allows for the "over-sizing" of indoor units, provided they aren't all used at full capacity at once.
Hybrid air handling describes the versatile capability of indoor units to be mounted in multiple orientations, such as floor or ceiling.
A hybrid multi-position air handler can be installed vertically or horizontally and works with various outdoor units.
Hydrophilic coil enhancement is a specialized coating on the aluminum fins that helps water droplets spread out and drain faster.
I
An installation kit includes all the necessary components like line sets, drain hoses, and electrical wires to set up a mini-split.
The auto-restart function ensures that your system returns to its exact previous settings automatically after a power interruption.
Intelligent de-icing cycles are automated routines where the heat pump temporarily reverses its flow to melt frost buildup on the outdoor coil.
A lift pump is a small mechanical device inside the indoor unit that pushes water vertically, allowing for drainage even when the unit is in a basement.
The inverter compressor is the "heart" of the outdoor unit, regulating the flow of refrigerant.
Eco-mode is a specialized operating frequency that limits the power consumption of the compressor to save money on utility bills.
Inverter precision modulation is the advanced capability of the compressor to adjust its frequency in tiny increments to match the cooling load.
Inverter technology allows the compressor to vary its speed rather than simply turning on and off, which significantly saves energy.
Soft start technology allows the compressor to ramp up its speed gradually, eliminating the massive "surge" of electricity common in old-fashioned AC units.
Frequency smoothing is the digital process of ensuring the compressor changes speeds without causing electrical "noise" or mechanical jitter.
L
Latent heat removal refers to the process of dehumidifying the air as it is cooled, which is essential for true comfort in humid climates.
Latent load dehumidification is the system's ability to remove water vapor from the air without significantly lowering the "sensible" or dry-bulb temperature.
A line set consists of two copper pipes that connect the indoor air handler to the outdoor condenser, carrying the refrigerant.
Line set covers are decorative PVC or plastic channels that hide and protect the refrigerant lines on the exterior wall.
Thermal insulation involves wrapping the copper refrigerant lines in high-density foam to prevent energy loss and "sweating" inside your walls.
Low ambient cooling allows an air conditioner to operate even when the outside temperature is very cold.
Low-profile aesthetics focus on HVAC designs that blend seamlessly into contemporary interior architecture without being obstructive.
The twin rotary design uses two balanced compression chambers to cancel out vibration and noise, making it our quietest compressor yet.
M
An M-coil is a type of evaporator coil shaped like the letter 'M' to increase the surface area for heat exchange.
A manifold gauge set is used to monitor the pressure of the refrigerant during installation and service.
Micro-channel heat exchange refers to the use of flattened tubes with tiny internal channels to increase the surface area for refrigerant cooling.
Diagnostic codes are alphanumeric messages displayed on the indoor unit or remote that help identify specific mechanical or electrical issues.
A mini-split is a type of heating and cooling system that consists of an outdoor compressor and one or more indoor air handlers.
Modular configuration allows for the customized assembly of indoor unit types—such as wall mounts, cassettes, and floor units—onto one system.
Modular condenser scalability describes the ability of our outdoor units to support a wide variety of indoor unit types and capacities simultaneously.
Multi-point distribution is the engineering method used to route refrigerant from a single outdoor unit to multiple indoor evaporators.
Multi-point sensing uses thermistors in the indoor unit, the remote control, and the outdoor unit to get a complete picture of your home's climate.
A multi-position air handler can be installed in several orientations: upflow, downflow, or horizontal.
Multi-stage air filtration is the process of using several layers of specialized mesh to remove dust, allergens, and odors from the air.
Our multi-stage purification uses a combination of high-density dust filters and specialized inserts to scrub the air of allergens and odors.
Harmonic balance is the engineering practice of ensuring that multiple compressors or fans in a large system do not create a "drone" or rhythmic vibration.
Condensate cascading is a drainage strategy for multi-story buildings where water from several units is routed into a single main drain line.
A multi-zone system connects a single outdoor condenser to multiple indoor air handlers, allowing for independent temperature control in different rooms.
Filtration layering involves using a primary dust filter followed by secondary active carbon or HEPA-style inserts to scrub the air.
Port synchronization is the process of mapping each indoor unit's communication cable to its corresponding refrigerant port on the outdoor condenser.
O
The MRCOOL Olympus 4th Gen Condenser is a reliable and efficient outdoor unit.
This wall-mounted air handler, the MRCOOL Olympus 4th Gen 12k BTU, is a versatile cooling solution.
This ceiling-mounted unit, the MRCOOL Olympus Cassette 12k BTU, provides 1 ton of cooling capacity.
This ceiling-mounted unit, the MRCOOL Olympus Cassette 18k BTU, provides 1.
This ceiling-mounted unit, the MRCOOL Olympus Cassette 24k BTU, provides 2 tons of cooling capacity.
The MRCOOL Olympus Cassette 9,000 BTU is a compact ceiling-mounted air handler.
The MRCOOL Olympus Duct 12,000 BTU is a hidden air handler for medium-sized rooms.
The MRCOOL Olympus Duct 18,000 BTU is a hidden air handler for large rooms.
The MRCOOL Olympus Duct 24,000 BTU is a hidden air handler for massive rooms.
The MRCOOL Olympus Duct 9,000 BTU is a hidden air handler for small rooms.
Omni-directional air diffusion describes a 360-degree discharge pattern that eliminates "dead spots" in a room’s climate.
Our Other Accessories collection includes specialized tools and parts for unique installations.
P
A Penta-Zone system is the ultimate multi-split solution, supporting five indoor units from a single condenser.
This five-zone system, the Bravo Milano Series 5 Zone 42k (9+9+12+12+18), is a whole-house powerhouse.
A pre-charged cased A-coil is an evaporator unit that comes ready for connection to a condenser.
A pre-charged coil comes from the factory containing the necessary refrigerant for a specific line length.
Q
A Quad-Zone system is designed to provide climate control for four distinct areas using only one outdoor unit.
The Bravo Milano Series 4 Zone 30k (9k x 4) is a balanced system for four small rooms.
The Bravo Milano Series 4 Zone 42k (9k+9k+12k+24k) is a highly customized solution.
Quad-zone scalability is the business and residential strategy of cooling four distinct areas using a single high-capacity external heat pump.
Quiet-mode is a specialized setting that drops the decibel level of both the indoor and outdoor units for overnight use.
R
R-410A has been the industry standard refrigerant for mini-splits for many years.
R-454B is a next-generation refrigerant with a lower global warming potential than previous standards.
Thermodynamic balancing involves optimizing the pressure and temperature relationship of the specific refrigerant used in our systems to maximize heat transfer.
Refrigerant charging is the act of adding cooling fluid to the HVAC system to reach the correct pressure.
Refrigerant flow optimization is the electronic management of the "Expansion Valve" to ensure the perfect amount of liquid reaches the evaporator.
Leak detection is a smart safety feature that shuts the system down and displays a code if it senses a loss of refrigerant pressure.
A refrigerant leak detector is a safety feature that alerts the user if the system's cooling fluid is escaping.
Refrigerant recovery is the process of removing refrigerant from a system and storing it in an external container.
Refrigerant recovery management refers to the system’s ability to "pump down" or safely contain refrigerant during maintenance or relocation.
A sub-cooling circuit is an additional heat exchange stage that cools the liquid refrigerant further before it reaches the expansion valve, increasing system capacity.
A sub-cooling coil is an extra section of the condenser that drops the refrigerant temperature well below the saturation point for higher efficiency.
Refrigerant glide refers to the temperature difference between the start and end of the evaporation process in certain blended refrigerants.
Manifolding is the design of the outdoor unit's internal plumbing that splits a single compressor output into multiple independent refrigerant lines.
Refrigerant superheat adjustment is a critical technical procedure used to ensure that only gaseous refrigerant enters the compressor, preventing liquid damage.
S
SEER2 (Seasonal Energy Efficiency Ratio 2) measures the cooling efficiency of an AC unit over a typical cooling season under new testing standards.
The self-cleaning function dries the evaporator coil after use to prevent the growth of mold and bacteria.
Self-diagnostics allow the unit to monitor its own health and display specific error codes if a problem is detected.
The Signature Series represents premium HVAC equipment with high-performance specs and durability.
The MRCOOL Signature Series 3 Ton Air Handler is a powerful ducted unit.
The MRCOOL Signature Series 5 Ton Air Handler is built for maximum capacity.
Sleep mode gradually adjusts the temperature throughout the night to match the body’s natural cooling cycle.
Slim duct units are hidden air handlers that connect to short runs of ductwork to cool one or more rooms discreetly.
Static discharge prevention refers to the grounding and shielding of the indoor unit’s circuit board to prevent damage from environmental electricity.
Static-pressure compensation allows a concealed unit to adjust its fan speed automatically based on the resistance of the ductwork.
A stud mount air handler is designed to fit between standard wall studs for a completely recessed installation.
Synchronized swing allows the horizontal and vertical louvers to move in a coordinated pattern for the most even air distribution possible.
Synchronized defrost logic allows a Multi-Zone system to intelligently time its heating pauses to melt ice on the outdoor coil without making the house feel cold.
Synchronous fan modulation ensures that the indoor blower and the outdoor condenser fan speeds are perfectly matched for the current load.
This specific configuration, the Bravo Milano Series 2 Zone 24,000 BTU (12k+12k), is balanced for two equal-sized rooms.
This powerful two-room configuration, the Bravo Milano Series 2 Zone 30k (12k+18k), is perfect for large master suites and living rooms.
The Bravo Milano Series 2 Zone 36k (18k+18k) is a powerful two-room system.
The Bravo Milano Series 2 Zone 36k (9k+24k) is a specialized two-room system.
The Bravo Milano Series 2 Zone 42k (12k+24k) is a heavy-duty two-room system.
The Bravo Milano Series 2 Zone 42k (24k+24k) is our most powerful two-room system.
The Bravo Milano Series 3 Zone 24k (9k x 3) is a balanced system for three small rooms.
This configuration, the Bravo Milano Series 3 Zone 30k (9k+9k+12k), is ideal for a three-bedroom layout.
This configuration, the Bravo Milano Series 3 Zone 36k (12k+12k+24k), is designed for large open homes.
This configuration, the Bravo Milano Series 3 Zone 36k (12k+18k+18k), is designed for homes with multiple large living areas.
The Bravo Milano Series 3 Zone 36k (9k+9k+18k) configuration is ideal for a three-room home with one large living area.
The Bravo Milano Series 3 Zone 42k (12k+12k+18k) configuration provides extra power for large rooms.
The Bravo Milano Series 3 Zone 42k (9k+9k+24k) configuration is ideal for a three-room home with one massive living area.
The Bravo Milano Series 4 Zone 36,000 BTU (9k x 4) is ideal for equalizing comfort in four smaller rooms.
This configuration, the Bravo Milano Series 4 Zone 42k (12k+12k+12k+18k), is designed for large households.
This configuration, the Bravo Milano Series 4 Zone 42k (12k+12k+24k+24k) is designed for massive homes.
This configuration, the Bravo Milano Series 4 Zone 42k (18k x 4), is designed for large homes with multiple large rooms.
The Bravo Milano Series 4 Zone 42,000 BTU (9k+9k+12k+12k) provides a custom cooling solution for a full house.
This five-head system, the Bravo Milano Series 5 Zone 42k (9k x 5), offers the maximum number of indoor units.
T
The TXV is a precision component that measures the temperature and pressure of the refrigerant to adjust the flow rate into the evaporator.
Thermal load balancing is the practice of distributing air conditioning power across various rooms based on their specific heat gain factors.
Thermal expansion compensation refers to the architectural planning for the physical growth and contraction of copper pipes as they change temperature.
Total Comfort logic is the final integration of all the system's sensors and algorithms to provide a seamless living experience.
Total system integrated logic is the "operating system" of the mini split that coordinates communication between all indoor heads and the outdoor unit.
A Tri-Zone mini-split allows for three indoor units to be connected to a single condenser.
Tri-Zone synergy occurs when three indoor units operate in perfect synchronization with one outdoor condenser to manage a medium-sized home.
Turbo mode is a function that runs the mini-split at maximum speed to reach the desired temperature as quickly as possible.
Turbo-cooling inertia is the system's ability to run at 110% of its rated capacity for a short period to rapidly drop the temperature in a hot room.
Turbo-speed allows the system to run at a higher-than-normal RPM for 20 minutes to rapidly reach your target temperature.
U
The UFC Multi-Zone refers to our collection of universal floor-ceiling air handlers in multi-room configurations.
UV-resistant encapsulation is the protective layering over the copper lines that prevents the sun's radiation from degrading the foam insulation.
UFC units are versatile air handlers that can be mounted either low on a wall near the floor or horizontally on the ceiling.
The Bravo Milano 12,000 BTU Universal Floor Ceiling is a versatile unit designed for medium-sized rooms.
The Bravo Milano 18,000 BTU UFC is a versatile, mid-sized air handler.
The Bravo Milano 24,000 BTU UFC is a high-power air handler for large open areas.
UFC geometry is the specific internal and external casing design that allows a unit to operate effectively whether it is standing vertically or hanging horizontally.
The UFC chassis is a specialized design that allows the indoor unit to be installed either horizontally on the ceiling or vertically on the floor.
Universal inverter technology allows a heat pump to vary its compressor speed rather than just turning it on or off.
Adaptability refers to the ability of our units to work with a variety of line-set lengths and diameters depending on the installation needs.
Universal bracket compatibility means that our indoor units are designed with standardized mounting patterns that fit almost any structural surface.
V
A vacuum pump is a tool used to remove air and moisture from the refrigerant lines before charging the system.
A variable-speed centrifugal blower is an indoor fan system that can change its RPM to match the specific airflow requirements of a room.
Vibration isolation involves using specialized mounting equipment to prevent the mechanical hum of a compressor from entering the home's structure.
W
A wall bracket allows the outdoor condenser to be mounted directly to the exterior wall of a building.
A wall-mounted indoor unit is the most common type of air handler for ductless systems.
This refers to a multi-zone system specifically using two wall-mounted indoor units.
Wi-Fi control allows users to adjust their HVAC settings via a smartphone app from anywhere in the world.
Z
Zonal thermal autonomy refers to the ability of a multi-room system to maintain independent climate settings without interference from other areas.
Zone-specific airflow routing is the ability of a multi-head system to direct air specifically where it is most needed within a room.