> For the complete documentation index, see [llms.txt](https://docs.betterbuilding.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.betterbuilding.io/user-guide/2d-building/building/hvac/hvac-templates/system-no.-1-ptac-packaged-terminal-air-conditioner.md).
# System No. 1 PTAC (Packaged Terminal Air Conditioner)
A Packaged Terminal Air Conditioner (PTAC), as defined in EnergyPlus HVACTemplate, is a self-contained climate control system commonly used in buildings such as hotels, apartments, and hospitals. It consists of an integrated unit that combines heating and cooling components in a single package, typically installed through an exterior wall.
The system uses a direct expansion (DX) cooling coil and may include electric resistance heating or gas boilers for heating. The PTAC draws outdoor air for ventilation and condenser heat rejection, while fans circulate conditioned air directly into the space, providing independent zone control. This configuration is particularly suitable for applications where decentralised, room-by-room temperature control is preferred.
A PTAC comprises:
* Plant HVAC component - Hot Water Loop
* Space HVAC component - Packaged Terminal Air Conditioner
The 'Select HVAC Template' form allows for multiple Spaces to be served. Clicking into the 'Spaces' field shows a list of available Spaces. Each selected Space will have one Packaged Terminal Air Conditioner Space HVAC component, providing independent climate control for that zone.
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