Outside air drawing in the house – second floor ductwork
I have a two-story house in Atlanta, GA, built in 1984.
I have noticed my supply and return registers have some air drawing in them on the second floor. I have a sealed gas furnace, 95% AFUE.
The HVAC vendor has told me the house draws air in as well. I have caulked around all registers and masticed all areas of ductwork and plenum. All my gas appliances are new furnaces (2), Tankless water heater, and gas range.
Question #1. If a house has a “stack effect” why am I seeing this happen?
Question # 2. Should I be concerned about this?
Question #3. Can this allow air to draw in from the plumbing vent pipes?
Question #4. How do fix this issue?
Question #5. Have I air sealed the house too tight?
Any thoughts would be appreciated..
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