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Which is a better system: a regular fan coil or high velocity fan coil?

user-1127593 | Posted in Mechanicals on

I am building a custom house for a customer. He will have in slab heating throughout the house, and I have suggested to my mechanical contractor to include the hi velocity fan coil. He says that the regular fan coil is better. Any advice would be greatly be appreciated.Thanks

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  1. GBA Editor
    Martin Holladay | | #1

    Your question is confusing. First of all, this house will have "in-slab heating." That usually means that you'll have a boiler to make hot water, and PEX tubing to distribute your heat.

    A fan-coil unit is a type of air handler that distributes hot air by blowing air over a copper coil that circulates hot water. (A fan-coil unit can also distribute cold air by blowing air over a coil that circulates cold water or refrigerant.) Why do you need a fan-coil unit? Is it for an air-conditioner? Please describe the home's cooling system.

  2. user-1127593 | | #2

    You will need a fan coil to circulate the air and also use it for a/c

  3. GBA Editor
    Martin Holladay | | #3

    1. An air handler can be used to circulate the air in a house, but if the house has hydronic heating, there is no need to do so during the winter.

    2. Neither an air handler nor a fan-coil unit will provide ventilation unless an outdoor fresh air duct is hooked up. If you go this route, be sure to include a Fan Cycler control and a motorized damper.

    3. Split-system air conditioners routinely include air handlers. If you want to select an efficient air handler, you should probably choose one with an ECM blower; for more information on this topic, see ECM Efficiency.

    Remember: if you want an efficient air-distribution system, every element of the system must be optimized. Inefficiencies are often due to bad duct system design and sloppy duct installation, so if you want an efficient distribution system, be sure that the ducts are properly designed and installed.

  4. user-1127593 | | #4

    Thanks Martin, I will check it out. Thanks for your advice.


  5. user-626934 | | #5

    Other things being equal...higher velocities = higher friction = more fan energy to overcome the friction = more noise = bad idea

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