Brian, if you're asking about putting a roof top A/C on your Boler... it won't hold the weight without internal bracing, like bows across the top. Otherwise, you're liable to end up with a big old unintended sky light. Others will pop in shortly.
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Donna D.
Ten Forward - 2014 Escape 5.0 TA
Double Yolk - 1988 16' Scamp Deluxe
It may hold the weight for a while, but the roof will start to sag, and the walls will bow. I am not sure how you can repair this damage.
I have seen them in the closet.