On Jul 10, 7:24*pm, Sam Takoy wrote:
Hi,

My central AC unit is on the 3rd floor and we get no relief on the first
floor. The only intake is in the ceiling of the second floor and the
HVAC specialist tells me that that's the problem. His proposed solution
is a second AC system for the first floor.

I'm thinking: why not take one of the outlet ducts and convert them to
an intake? Crazy enough to work?

Thanks,

Sam

Far too little info to even guess. It depends on the layout of the
house,
the location and number of all the returns and outlets, if the
existing
system is of sufficient capacity for the house, etc. If the existing
system is large enough and it's possible to add significant return
to the first floor, that will help. If the system is undersize or
marginal, then a seperate system for the first floor sounds
logical.

I can tell you that turning one outlet duct into a return is unlikely
to make a material difference. You have no returns on the
first floor. Just taking one outlet and making it into a return is
not going to have enough duct capacity to do much. And you
will obviously loose that outlet, which isn't what you want to do
either.