Does alloy matter?

Brb77usmc

In all my research of hydronic radiant heating systems, specifically the use of aluminum heat transfer plates, I have yet to see anyone discuss the alloy of aluminum used. I’m curious if the purity of the aluminum has a quantifiable effect on the thermal conductivity, ie the efficiency, of these systems? I believe only two manufacturers openly disclose their alloy and I’m pretty sure the rest just use aluminum flashing which is primarily 3025 and 3105 series. A follow up question could be does increased thickness of inferior alloy compensate?

Jamie Hall

First, the type of aluminium alloy will have almost no effect on heat transfer. I doubt that anyone uses aluminium flashing, although various thin sheets may be used. Increased thickness of "inferior" (nothing wrong with the 30nn and 31nn series alloys) alloy won't compensate; what the manufacturer is -- or should be -- looking for is the corrosion resistance of the alloy, and that varies all over the place.