Two-pipe and four-pipe fan coils: what is the difference

Fan coils can be two-pipe or four-pipe, depending on how they are connected to the hydraulic network.

Two-pipe

The same network carries either hot or cold water, depending on the season and the heat pump operation.

Four-pipe

There are separate heating and cooling circuits, allowing for simultaneous different requirements in different spaces.

Advantages and limitations

The two-pipe system is simpler and more economical, while the four-pipe system offers greater flexibility but requires a more complex installation.

Selection

The choice depends on the needs of the building, the type of heat pump, and the control strategy.