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Where to put A/C air handler and blower

user-7571894 | Posted in General Questions on


Currently designing our new family home. A lot of 3 level homes (basement, first floor, second floor) in vancouver canada have AC on the first and second floors. Builders are placing air handlers on the second floor in closets (2′ x 3′) likley due to the cost of running ductwork, but I’m hearing it’s better practice to place the unit in the basement.

Our house will have a seperate hrv system as well with the unit located in the laundry in the basement.

My question is, should I be placing the ac air handler on the top floor or in the basement?

Approx square footage of the home is 2,800 (including the basement).

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  1. Expert Member
    Akos | | #1

    Generally it is the basement that has the most "low value" space. I see little benefit of having the HVAC elsewhere. It also tends to be quieter, I've lived in a place before where the HVAC was in a closet in the den, does make a lot of noise.

    The important part is large return near the 2nd floor ceiling, a detail commonly skimped so you end up with bedrooms that are too hot in the summer.

    This is mostly for "traditional" hvac setups. If you are going with a ducted mini split heat pump, those units can be placed anywhere as they are much quieter.

  2. walta100 | | #2

    I like the basement. With 2 stories and a basement I think you want a zoned system with the second floor as one zone. Even better is a separate system for the second floor.

    After rereading your question, I wonder if the unit in the laundry is really doing the basement and first floor?

    Of course the most important decision is what size equipment do you need? Hint bigger is not better and to small is worst of all. For this you need a manual J calculation. These calculations are generally worth what you pay for them. So if the contractor prepares one for free it is likely worthless. You are looking for a third party report.


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