In-depth articles on every HVAC system, component, and concept.
Inverter-driven heat pumps represent the most significant advancement in residential and light commercial HVAC technology in decades. Unlike traditional single-stage systems that cycle fully on and…
What EPA 608 Certification Is and Why It Matters
EPA Section 608 certification is a federal requirement for any technician who maintains, services, repairs, or disposes of equipment containing regula…
HVAC work ranks among the most hazardous occupations in the construction and service trades. Technicians routinely encounter voltages capable of causing fatal electrocution, handle refrigerants that…
What Is a Cooling Tower?
A cooling tower is a heat rejection device that transfers waste heat from a building or industrial process to the atmosphere through the evaporation of water. Cooling tower…
What Is Psychrometrics and Why Does It Matter?
Psychrometrics is the study of the thermodynamic properties of moist air. For HVAC technicians, it is one of the most essential branches of applied scie…
What Fan Laws Are and Why They Matter
Fan laws are a set of proportional relationships that predict how changes in fan speed or air density affect three critical performance variables: airflow, press…
What Is Refrigerant Recovery and Why Does It Matter?
Refrigerant recovery is the process of removing refrigerant from an HVAC/R system and storing it in an approved external container for reuse, re…
HVAC filters serve two essential functions: protecting heating and cooling equipment from debris and removing airborne particles that affect indoor air quality. The three most common filter types foun…
Indoor coil icing occurs when the evaporator coil inside an air conditioning system drops below 32°F (0°C) and moisture from indoor air freezes on its surface. What starts as a thin layer of frost c…
A rooftop unit (RTU) is a self-contained HVAC system designed for outdoor installation, typically on the roof of a commercial building. RTUs house all major components in a single cabinet: compresso…
Designing an HVAC system for new construction is fundamentally different from retrofitting an existing building. In new construction, every decision about the building envelope, mechanical systems,…
The Role of the Compressor in HVAC Systems
The compressor is the mechanical heart of every air conditioning and refrigeration system. It pressurizes refrigerant vapor, driving the thermodynamic cyc…