I agree that penetrations to the outside need to be sealed properly. My comment was that sealing the penetrations into the metal housing isn't necessary if the "box" protruding from the house and the install of the exhaust pipe was done properly. Every one of these fireplaces that I have looked at, because of cold air leaking, has been because the exhaust pipe hasn't been sealed when installed. I like my fireplace but think bad installs have given them a bad name.
Q
Nailed the problem!
Q