Close this search box.

2 Pipe vs 4 Pipe System fan coil unit

  • 4-pipe-fan-coil-system-schematic

    Last Updated on January 22, 2024 by Shawn Lee

    Divide the fan into two pipes, three pipes, and four pipes according to the quantity of water system layout, which refers to the form of the water system in each building.

    Two fan coil unit :

    the whole building water system adopts a water inlet pipe and a water outlet pipe. This system is supplied with cold water in summer and hot water in winter. Such a system can bring warmth to the whole area in cold winter and coolness in hot summer.

    Two-pipe fan coil unit
    Two-pipe fan coil unit

    Four control fan coil unit :

    Two surface coolers are present inside the fan coil, and each group of surface coolers connects to a water inlet pipe and a water outlet pipe.
    From the appearance, we can see that the fan coil has two inlet pipes and two outlet pipes. Mostly, hospitals, hotels, and other places with high environmental requirements use fan coil units with this structure.
    Four-control fan coil units can adjust the indoor temperature at will and can send out cold air to reduce the indoor temperature or hot air to increase the indoor temperature according to the needs of indoor personnel.

    Comparison of two-control fan coils and four-control fan coils:

    Two-control fan coil units have simple operation and management, convenient construction, and reduced construction costs. However, they do not allow switching between cooling and heating modes. Only cold air or hot air can be provided.
    Four-control fan coil units have complex operation and management, complicated construction, and high construction costs.

    However, indoor users have more choices, and they can arbitrarily switch the hot and cold modes to adjust and change the indoor temperature environment according to their individual needs.

    4 pipe fan coil system schematic
    4 pipe fan coil system schematic

    What environment is suitable for two controls? What building environment is suitable for four controls?

    Adopt two control water systems when the air-conditioning system running throughout the year only requires the conversion of cooling and heating according to the season.
    High-rise buildings, especially high-rise shopping malls, amusement parks, and cinemas, are large-scale construction sites with relatively dense personnel. Using two control systems can meet most indoor temperature regulation requirements. Multi-story or high-rise civil buildings widely use the air-conditioning water system.

    During the whole year’s operation, use an air-conditioning system with a four-pipe water system when the cooling and heating conditions frequently alternate or need to be used simultaneously. The four-control fan coil unit suits the situation where the standard of the construction site is high and the budget meets the requirements.


    Leave a Reply

    Your email address will not be published. Required fields are marked *

    Please enter your email to let us contact you

    We will contact you within 1 working day, please pay attention to the email with the suffix “”