Re: Noisey floor vent
It's not uncommon to have velocity noise when new efficient furnaces are installed ..... usually the HVAC company is economizing the install for a variety of reasons.
As already mentioned there can also be noise from the ducting and trunks expanding and contracting with higher velocity air moving through them.
However, depending on the furnace there may be a multi-speed or variable speed blower motor installed which allows a slower speed without really any issues with tripping the high limit. Lowering the blower motor speed will reduce the velocity noise .... but ..... this also impacts the balancing of the system's air flow.
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