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Question about taping to a Mitsubishi ducted indoor unit

I have a ducted indoor unit that needs to be taped where the plenum attaches to the supply side of the machine and the way Mitsubishi has the system made it has thin foam all over that side of the machine.

What is the correct way to tape/seal that section? I don't mind using mastic, but I'm not sure it would be the preferred first option.

This is roughly the area I am talking about.


  • mattmia2
    mattmia2 Member Posts: 3,702
    Are you talking about that transition to the small essentially trunk? What are you trying to accomplish?