When we finished our basement 2 years ago, we had put vent covers on all the vents in the house, including the second floor, to try to contain the dust. While I think they worked somewhat, we still had construction dust upstairs. Our only furnace is in the basement. We changed all the filters in the furnace immediately after construction was done and again 6 months later and there was still a ton of junk in there. We have a lot of allergies in our family so we had the ducts cleaned too several months later. I personally would clean both systems.

Where are the return filters for each system? Filters should be checked and replaced ASAP. Filters are for indoor air quality and to protect Evap coil and blower motor.

IMO

If your system is well sealed, the only duct that should have dust in it is the return ducts, and it has a filter before it connects to the HVAC. That filter will need to be replaced more frequently, but is supposed to catch the dust. If working properly, very little dust should make its way to the supply ducts. YMMV.

Bruce

If you sealed the ducts before the reno, then it shouldn't be too much of a problem. Just changing the filters should be good, but if not then it may be worth it to get them cleaned, especially if you have any allergies or sensitivities to dust.

Twintech Heating & Cooling

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