Fan coil unit vs fan coil terminal

Reading Architect’s Studio companion and I noticed that they describe an example of All-Water system as a Fan coil terminal which appears to be different from a fan coil unit (which is in the ceiling of a space and helps distribute air around found in all air systems)

Can someone please verify my understanding of that?

Additionally can someone point me to a resource(s) of where I can find examples of specific systems that are hydronic vs air vs other types?



Hi @Shikha that’s a good question! @coachmarkbailey @coachlizschneider are you able to help verify?

Hi @Shikha , from my understanding and some research here are my findings on differentiating the two:

Fan Coil Units (commonly called FCU’s) are a self-contained unit composed of a fan and a heating or cooling heat exchanger. The fans in FCU’s are, unlike in air handling untis, put inside the same space as the fan coil unit. These are smaller units that re-circulate air through a building instead of taking air from the outside.

Smaller Fan Coil Units are sometimes called Terminal Units because they are viewed as little air handling units for single rooms, therefore the fan would be separate from the coil portion of the unit.

A few other differences between AHU’s and FCU’s:

  • FCU’s only have one fan, where AHU’s have multiple fans
  • FCU’s are generally used from controlling the space where they are installed. When AHU’s are the source in a larger system.
  • FCU’s don’t generally use ductwork to cool or heat air. The fan pulls the air over the coil.

I also recommend checking out “The Engineering Mindset” YouTube videos, in addition to the Black Spectacles video series on AHU’s/RTU’s/FCU’s. The acronyms are so similar but very important to distinguish between the three.

I hope this helps!