Return suction

New condo. Two AC uinits. One is working fine. The other one does not have heat. They probably just forgot to connect it.


On the unit with no heat there is excess suction which causes the door to slam shut. The unit with heat has is normal. Both returns are the same size. Any thoughts on this one?

What door?

Are the returns local or remote. What you are describing sounds as if you may be dealing with two different sized blowers, contractor may have used what he had in stock rather than what should have been used as for size and CFM


Recommend having HVAC guy check and repair, to your Client.

My first thought is, a blockage/restriction in the blower compartment or in the airstream. Just guessing, without a whole lot of info.

Good Luck

I am not thinking blockage or restriction as this reduces air flow. To many CFM, blower may be multi speed and wired on high speed or simply oversized. Are both furnaces the same model #

“What door” - Closet door

“Are the returns local or remote.” - Local

“Are both furnaces the same model” - We dont see too many furnaces down here. both are Trane air handlers, this one was a five ton.

Thanks for all the quick responses.

Am I understanding you correct this furnace is installed within a closet and it is pulling the door to the closet closed. There should be no return opening within the closet for any reason. Bad connections or other wise