2,400+ Definitions
HVAC GLOSSARY
Every HVAC term, acronym, and industry phrase — defined in plain English.
Hot Aisle Containment
Hot aisle containment isolates warm return air from server equipment…
Hot Gas Bypass
A hot gas bypass is a refrigeration control method that…
Hot Gas Bypass Valve
A pressure-regulating valve that diverts discharge gas back into the…
Hot Gas Defrost
A defrost method used in heat pump outdoor units where…
Hot Gas Defrost Solenoid
An electrically actuated valve that opens during the defrost cycle…
Hot Gas Line
The hot gas line, also known as the discharge line,…
Hot Gas Reheat
Hot Gas Reheat (HGRH) is a dehumidification strategy used in…
Hot Surface Igniter
A hot surface igniter is an electric heating element that…
Hot Water Coil
A hot water coil is a heating heat exchanger that…
Hot Water Plant
A Hot Water Plant is a centralized heating facility that…
Hot Water Recirculation Pump
A hot water recirculation pump continuously circulates heated water through…
Hot Wire
The hot wire carries electrical current from the source to…
Hot Wire Anemometer
A hot wire anemometer measures air velocity by detecting cooling…
Hot-Wire Anemometer
A velocity measurement instrument that senses airflow by the convective…
Hourly Analysis Program
Hourly Analysis Program (HAP) is an energy simulation methodology and…
Housewrap
Housewrap is a weather-resistant membrane installed over building sheathing to…
HRV (Heat Recovery Ventilator)
A Heat Recovery Ventilator (HRV) provides controlled fresh air ventilation…
HSPF
HSPF (Heating Seasonal Performance Factor) measures the total heating output…
HSPF2
HSPF2 (Heating Seasonal Performance Factor 2) is the federal standard…
Humidifier
A humidifier is an HVAC component designed to increase the…
Humidifier (Whole-House)
A whole-house humidifier adds moisture to the air distributed through…
Humidistat
A humidistat is a control device that measures indoor relative…
Humidity
Humidity is the amount of water vapor present in the…
Humidity Data Logger
A humidity data logger continuously records relative humidity (RH) levels…
Humidity Effectiveness
A performance metric for heat and energy recovery ventilators expressing…
Humidity Ratio
The mass of water vapor present in a unit mass…
Humidity Sensor
A humidity sensor detects and measures moisture content in air,…
HVAC API
An HVAC API is an application programming interface that enables…
HVAC App
An HVAC app is a mobile application that enables users…
HVAC Coordination
HVAC Coordination is the collaborative process of aligning heating, ventilation,…
HVAC Diagnostics Remote
HVAC diagnostics remote refers to the ability to perform system…
HVAC Drawings
HVAC Drawings are specialized technical documents that illustrate all components…
HVAC Industry History
HVAC Industry History documents the evolution from steam heating in…
HVAC Installation
HVAC installation is the complete process of placing heating, ventilation,…
HVAC Log Book
An HVAC log book records the complete service history of…
HVAC Predictive Maintenance
HVAC predictive maintenance uses data analysis and machine learning to…
HVAC Scheduling App
An HVAC scheduling app enables users to program heating and…
HVAC Specification
An HVAC specification is a comprehensive written document that details…
HVAC Submittal
An HVAC submittal is a collection of documents and product…
HVAC System Design
HVAC System Design is the comprehensive engineering process of determining…
HVAC Tune Up
An HVAC Tune Up is a focused service visit that…
Hybrid Heat Pump
A hybrid heat pump system combines both an electric heat…
Hybrid Inverter
A hybrid inverter seamlessly manages power from solar panels, battery…
Hybrid Solar System
A hybrid solar system combines grid connection with battery storage,…
Hybrid Ventilation
Hybrid ventilation combines natural ventilation with mechanical systems to optimize…
Hybrid Water Heater
A hybrid water heater combines heat pump technology with electric…
Hydraulic Balancing
Hydraulic balancing is the process of adjusting flow rates through…
Hydraulic Separator
A device installed between a boiler plant and distribution system…