Glossary of Terms

AHU: Air handler unit.

Back Flow Testing: Certification of all types of back-flow devices.

BIM: Building image modeling.

BTU: (British thermal unit) Unit of measure for furnace sizing.

CAD: Computer-aided drafting.

Efficiency Percentage: Amount of heat from a fuel burn that stays in the home.

EPA: (Environmental Protection Agency) The US government agency in charge of environmental issues.

FLIR: (forward looking infrared) A type of camera that analyzes home heat loss and diagnoses areas of overheating.

HITS: High Impact Training in Safety.

HVAC: Heating, ventilating, air conditioning.

LEED: Leadership in Energy and Environmental Design.

NATE: (North American Technical Excellence) The leading HVAC training/certification program in the industry and the only test accepted by the entire industry.

RMGA: Rocky Mountain Gas Association.

ROI: Return on investment.

RTU: Roof top unit.

SEER: Seasonal energy efficiency ratio.

SMACCNA: Sheet Metal and Air Conditioning Contractors National Association.

Tonnage: Unit of measure for air-conditioner unit sizing.

VRF: Variable Refrigerant Flow

Variable refrigerant flow systems (VRF) are a more sophisticated version of the minisplit HVAC system used throughout the world. They distribute the refrigerant instead of piping hot water and chilled water to each fan coil unit (FCU) or air handling unit (AHU). By supplying different amounts of refrigerant to evaporators, the systems provide simultaneous heating and cooling.