I hooked mine into my exhaust and the a/c didn't cool properly. .It seemed to work ok at first but the temps gradually began to rise.. Maybe if you hooked it up to the very end of your exhaust (where it goes thru the wall) you might get away with it. You would be better off exhausting it separately with the original duct etc. that came with the a/c. The instructions that came with my a/c warned against altering the exhaust or lengthening it in any way, and it proved to be good advice.