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Community and Q&A

Central vac venting

NormanWB | Posted in General Questions on

I am in the process of building a tight house that will have a central vacuum. I am concerned about makeup air and wonder if running the exhaust into a conditioned crawlspace is ok. Of course that would introduce fine particles into the area, which would probably be bad, so what is my alternative? A motorized vent to the outside connected to the power switch of the vacuum?

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  1. user-2310254 | | #1

    I have my central vac motor and canister installed in a storage room that is outside the house. In your case, you could run an exhaust pipe from the canister to a dampered end cap mounted on the exterior.

  2. user-1072251 | | #2

    Emptying the dust and particlas from your vacumm into the house is a bad idea; expecially in a tight house! It must be exhausted outside the house. Perhaps the dealer might be able to help find a damper if it's needed; I'm not convinced the damper is needed.

  3. GBA Editor
    Martin Holladay | | #3

    Both solutions have disadvantages. If the canister is inside the home's thermal envelope, there is the possibility that emptying the canister will release dust into your home.

    If the canister is outside of the home's thermal envelope, on the other hand, operating the vacuum cleaner will depressurize the house, putting combustion appliances at risk of backdrafting. You may not be worried about this risk, however, if your house doesn't have any atmospherically vented appliances.

    There's something to be said in favor of the simplicity of a conventional portable vacuum cleaner.

  4. kyeser | | #4

    We have central vac in our relatively tight house, I think w came in around .9ACH50. I installed the canister in a heated storage room in the garage that vents directly outside. The system works terrific. I notice a lot less dust in our house than other peoples.

    I highly recommend central vac, wouldn't build a house without it.

  5. Chaubenee | | #5

    Central vac has the advantage of putting the dirt into a bag and the air that passes through that bag can be forced outdoors. Your house will have much better indoor air quality. We love our. Don't undersized the motor whatever you do. Put the air through the outside. My canister is in the basement and the 2" pvc pipe passes through the concrete basement wall. The dust and the noise end up outside. When vacuuming you can crack the door. We don't find it neccesary. We don't vacuum every day so the heat loss should negligible. My house had a blower door test that came back .60 ach. Furthermore I use 550 gallons of propane a year to heat the house and water. My house is 4800 sf. Details matter. But you don't need to sacrifice the awesomeness of a central vac system in a tight house that's is sealed.

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