Just wondering what you guys are using to seal around these components? Here in my area about 80% of the residential units are installed as upflow with the units in a utility closet in the garage. The return is under the slab and the supply is ran using fiber board mains with flex duct branches in the attics. Anyhow, most of the installers are using alum. foil tape to seal around the joints on the furnace, coil, filter and duct in the utility closet. It just doesn't look right having a high dollar system all taped up.