Ceiling & floor cold air returns

[boo coo tracks]

I have to rehab enclosed sun porch. Currently have 3 floor cold air returns, (1 story house & basement) I think 1 cold air return could be moved to ceiling thus giving a better air flow through-out the house. This would be easy to box in during remodel. This question is it worth the effort for heating & AC??
You thoughts please.
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[phbsales]

Are the supply registers mounted in the ceiling? If they are, then installing a return in the ceiling could prove more detrimental to good cooling of the space.

 

[boo coo tracks]

Both supply & returns are in the floor. This house probably had a gravity flow in the basement before High eff. was installed.
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