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Old furnace fan for use with mini split

sallyogally | Posted in General Questions on

Our gas furnace was dying so we put in a mini split and a gas insert in the fireplace. Can we use the furnace fan to distribute the heat to the upstairs rooms?

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  1. 1869farmhouse | | #1

    Not well. Changing the temperature of a room requires a source point where heat is a significantly higher temperate than the ambient air. Unless you could put a return right by the mini split, I think you’d just be wasting energy blowing air around. Those fans use a not insignificant amount of electricity if not ECM.

  2. maheatpumpguy81 | | #2

    I'll second Austin G's advice. I installed a Panasonic exhaust fan right near the indoor unit of a minisplit and sent the duct to another room. It does next to nothing for heating. The only benefit is air circulation, but even that is minimal with the CFM the exhaust fan is rated for.

    Heat rises tho, so maybe you'll get a 1-2 degree bump if you do this. Hard to say. But, there have been some building science articles on this and I believe you'd need a really well insulated house to have a fighting chance with this tactic.

  3. sallyogally | | #3

    Thank you both so much. Glad to not waste electricity if it won't do much in the way of heating.

  4. walta100 | | #4

    Generally getting heat up is not a problem, now getting the cool air upstairs that could be something to think about.


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