> 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.-2-pthp-packaged-terminal-heat-pump.md).
# System No. 2 PTHP (Packaged Terminal Heat Pump)
A Packaged Terminal Heat Pump (PTHP), 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 a reverse-cycle heat pump for heating, allowing it to provide both cooling and efficient heating from a single refrigerant circuit.
The PTHP draws outdoor air for ventilation and heat exchange with the outdoor environment, 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 with energy-efficient heat pump heating is preferred.
A PTHP comprises:
* Space HVAC component - Packaged Terminal Heat Pump
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 Heat Pump Space HVAC component, providing independent climate control for that zone.
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