> 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/fan-coil-unit-system-water-heating.md).

# Fan Coil Unit System (Water Heating)

A Fan Coil Unit System (Water Heating) is an HVAC configuration employing fan coils for air distribution. 

<figure><img src="/files/q56mModqxI0BviSDnsi6" alt=""><figcaption></figcaption></figure>

It utilises hot water from a central source for heating, providing energy-efficient climate control in buildings. It is comprised of:

* Condenser Water Loop
* (Optional) Air Handling Unit
* Hot Water Loop
* Chilled Water Loop
* Fan Coil Unit(s)

The 'Select HVAC Template' form provides options, to allow the user to configure the system with:

* Zone Reheat Type (Electric or Hot Water)
* Optional connection to a central Air Handling Unit (for outside air supply)
* A single AHU connected to multiple Fan Coil Units or multiple AHUs connected to multiple Fan Coil Units
* Choice of Spaces for Air Terminals

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Only available on Premium Plan.  Please reach out for further [support.](/support-and-training/contact-us.md)
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