I have a 3 year old home and the builder installed a return vent on the main intake trunk that connects to the furnace. This is super annoying for a few reasons:
- It pressurized the first floor. This is very noticeable on the first floor when opening the door to the basement. You feel the rush of air being sucked into the basement.
- It pulls odors and dust from the basement into the first floor.
- It is heating the basement unnecessarily by pulling hot hair through the underside of the basement door
I tried capping the return vent but it resulted in the blower motor making a slight noise. I mentioned this to my HVAC guy and he said this is a sign of the motor working too hard and i should remove the cap. He said there is insufficient return air coming from the first floor. I will note that prior to the cap, i have heard this same noise coming from the unit from time to time.
We have 2 return air registers on the first floor for about 1500 square feet of living space. They measure 11x11 and 10x13 but the 11x11 one seems to be doing most of the work.
What is the best way of solving this problem? My HVAC guy offered an approach of turning the basement into a full zone and utilizing dampers to have that furnace operate both the basement and first floor zones. This would be useful for finishing the basement which is something I am interested in. He was a bit hand wavey about how he would solve for the pressurization problem. I would really need to see a full system diagram to be confident. Is there a simpler solution to this problem?