@ai6yr As someone who unwittingly bought a house from an avid DIYer, please do not DIY. The HVAC techs were amazed yesterday looking at my house, and one of them is old enough to have a 97yo mom. He has Seen Some Stuff. (I have an HVAC duct that runs OUTSIDE MY HOUSE. It's a wonder that when it's 0 deg outside it's as high as 63 in the room served by that duct.)
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