I've seen homes that had inadequate duct systems, where they cut a big return in at the basement so the A/C would work properly...sight unseen, I don't know if this is the case. I hope there isn't a gas hot water heater in the same area. The solution to the door pulling shut may be to mount a grille on each side of the lower part of the door. If you have concerns, it may be worth paying someone that knows duct systems to come out and spend an hour looking around and offering solutions.

What size return do you have upstairs?

Upstairs return barely gets any airflow, which is what concerns me.

Upstairs: 20x20
Middle Floor: 22x22
Basement: 14x14 (on ceiling right near furnace)

None of the grills have filters; the filter is located at the air handler. This is a 3.5 ton system.

I was hoping someone was familiar with the return air setup of typical 3 story homes. Logically, I guess the upstairs return would get less airflow because it is farther away from the air handler, but to what extent? Putting my hand by it I can barely feel it moving any air, but I do see some dust particles moving inside so I know it it bringing in air. Do cold air returns using bring in the most air in the basement?

Thanks in advance!!

What type of heat and how do you heat your water?

Returning from the basement can be against codes. If you heat with gas or oil there is always the possibility to pull flue gassed through the water heater chimney or draft diverter if the return is in the same room as the furnace or there is insufficient combustion air in the space.

Have a contractor check the pressure in the return duct. It may be possible to "redirect" where the air is being pulled from by blocking the basement return. Ideally, you want 60% of the return air to come from the high point in the system. Your description would indicate that is not happening.

The only time you want to return from the basement is if you wife has cold feet in the winter and she is spending a lot of time in the basement.

Good luck,

Thanks for the advise. The home is all electric so no worries on the code side of things.

Ryan,

First of all you want a balanced system, if as you stated, you have a door between the basement and first floor, then the amount of return should equal the amount of the supply. Then your door won't slam. If there is a hard round duct somewhere between the basement return grille and the main return duct, you can put a manual balancing damper in pretty easy. If it's a rectangular duct, measure the size, you may have to have a contractor make you one. Now with a damper on the return you can damper down the return to match the supply. By dampering down the basement more return airr will be pulled in upstairs.

It's all a matter of balance,

Take Care,

Dan Martyn

Thanks Dan. I am going to call a professional in for an analysis of the whole system as I am considering replacing it.

Yea I am going through the same thing, I am wondering that if you can close the grill do you need a damper, just a thought