A dishwasher is a single object. A heat pump has an indoor part, and outdoor part, and (at least) two tubes between them. Those tubes can carry one of several r

A dishwasher is a single object. A heat pump has an indoor part, and outdoor part, and (at least) two tubes between them. Those tubes can carry one of several refrigerants (with attendant oil contamination), water, or glycol solutions. Or occasionally air. There are quite a few standards for connecting all of these, although the standards for air appear to literally be duct tape [0] or sticky goop called mastic. And refrigerant, which is the most common choice, is under high pressure and needs special handling. [0] I mean real duct tape: the UL181 stuff. The world is full of kinds of tape, and many of them are excellent. I’ve never seen anything I would call excellent duct tape. It doesn’t conform well to irregularities, and it doesn’t seem to have anywhere near the stretchiness required to actually seal the inherently curved gap between round ducts.