2,400+ Definitions
HVAC GLOSSARY
Every HVAC term, acronym, and industry phrase — defined in plain English.
Industrial Ventilation
Industrial ventilation systems remove contaminants, heat, humidity, and harmful substances…
Inertia Base
An inertia base is a massive concrete or steel platform…
Infiltration Rate
Infiltration rate measures the volume of uncontrolled outside air entering…
Inflation Reduction Act
The Inflation Reduction Act (IRA), enacted in August 2022, represents…
Infrared Heater
An infrared heater is an industrial heating device that produces…
Infrared Inspection
Infrared inspection identifies equipment problems and energy losses by measuring…
Infrared Thermometer
An infrared thermometer measures surface temperature by detecting thermal radiation…
Insulation Resistance Test
An insulation resistance test measures the effectiveness of electrical insulation…
Integral Control
Integral control continuously adjusts valve position based on the accumulated…
Integrated Collector Storage
Integrated collector storage (ICS) systems combine solar collection and thermal…
Integrated Design
Integrated design is a collaborative planning approach where HVAC engineers,…
Integrated Energy Efficiency Ratio
Integrated Energy Efficiency Ratio (IEER) measures the cooling efficiency of…
Integrated Part Load Value
Integrated Part Load Value (IPLV) represents chiller or air conditioning…
International Energy Conservation Code
The International Energy Conservation Code (IECC) is a model building…
Internet of Things
The Internet of Things (IoT) is a network of physical…
Inverter Efficiency
Inverter efficiency measures the percentage of DC power successfully converted…
IO List
An IO List (Input/Output List) documents all physical connections between…
IoT Sensor
An IoT Sensor is a connected device that continuously measures…
IPLV
IPLV (Integrated Part Load Value) measures chiller efficiency across varying…
IRA HVAC Rebates
IRA HVAC Rebates are federal rebate programs established under the…
IRC
Definition The International Residential Code (IRC) is a model building…
Irradiance Correction
Irradiance correction adjusts solar panel performance calculations to account for…
Isentropic Compression
Isentropic compression is a theoretical frictionless compression process where entropy…
Isentropic Efficiency
Isentropic efficiency is a thermodynamic performance metric that compares the…
Island Mode
Island mode occurs when a grid-tied solar system continues operating…
ISO Class
ISO Class is a designation from the ISO 14644-1 standard…
Isolated System
An isolated system permits no exchange of energy or mass…
Isolation Room
An isolation room is a specialized hospital space with negative…
Isothermal Process
An isothermal process is a thermodynamic process in which the…
ITC
ITC stands for Investment Tax Credit, a federal incentive allowing…
Jet Fan
Jet fans are axial fans mounted in tunnel ceilings that…
Joule Thomson Effect
The Joule-Thomson Effect describes the temperature change that occurs when…
Journeyman Technician
A journeyman technician is a skilled HVAC professional who has…
Kigali Amendment
The Kigali Amendment, adopted in 2016 as an addition to…
Kilowatt
A kilowatt (kW) is a unit of power equal to…
Kilowatt Hour
A kilowatt hour (kWh) is the standard unit measuring electrical…
Kitchen Exhaust
Kitchen exhaust is the mechanically induced removal of heat, moisture,…
Kitchen Fire Suppression
Kitchen fire suppression is an automated safety system designed to…
Kitchen Hood
A kitchen hood is a ventilation device mounted above cooking…
Kitchen Ventilation
Kitchen ventilation is the complete system of air removal and…
KNX
KNX is an open-source international standard (ISO/IEC 14543-3) for home…
kW
A kilowatt (kW) measures electrical power, representing 1,000 watts of…
kWh
A kilowatt-hour (kWh) is the standard unit measuring electrical energy…
Laboratory HVAC
Laboratory HVAC systems are specialized climate control installations designed to…
Laminar Flow
Laminar flow refers to air movement in parallel layers at…
Laser Alignment
Laser alignment is a precision measurement technique using laser beams…
Latent Heat
Latent heat is the thermal energy absorbed or released when…
Latent Heat of Fusion
Latent heat of fusion is the quantity of thermal energy…