this has to do with heating, ventilation and air conditioning (HVAC) systems

related sources:

Introduction to Heating, Ventilation, and Air Conditioning
pages.uoregon.edu/ftepfer/SchlFacilities/SchlFacHVAC.html
Coil = radiator-type device that exchanges energy with air, heating or cooling it. ... Zone = an area which can be heated and or cooled to its own temperature.

Heating, ventilation and air conditioning zone controls
www.cooltecservices.co.uk/Downloads/ECAScheme.pdf
Heating, ventilation and air conditioning zone controls. 1 Eligibility for ECAs is based .... electric underfloor heating, provided by coils buried in the floor. This can ...

Simulation Detailed Results - DesignBuilder
www.designbuilder.co.uk/helpv2/.../Simulation_Detailed_Resu...
Doors and Vents - Sum of heat gains to the zone from door and vent inner surfaces. ... as a heating coil energy delivery when mechanical ventilation is involved.

Simulation Detailed Results - DesignBuilder
www.designbuilder.co.uk/helpv2/.../Simulation_Detailed_Resu...
Doors and Vents - Sum of heat gains to the zone from door and vent inner surfaces. ... as a cooling coil energy delivery when mechanical ventilation is involved.

Input Output Reference — EnergyPlus 8.0
bigladdersoftware.com/epx/docs/8-0/input-output.../page-028.html
Zone Mechanical Ventilation Cooling Load Decrease Energy [J]. Zone Mechanical .... Cooling Energy. Energy removed from air loop by Cooling Coils (Joules) ...

CAV Ventilation System Improvement
wea-inc.com/pdf/cav.pdf
Central fans typically blow the air across heating and sometimes cooling coils into ductwork which brings the fresh air to the large common zones in the building.