All I could find at Lowes was 1/4" copper tubing. I'm assuming there's a reason aluminum is specified (or I'll buy the copper!), but I can't find it. Where do those of you who know these things get it?
I have always seen aluinum in this application. Wish I could say why... Try a local HVAC company. Maybe they can at least answer why. Seems copper would be OK...Thermal expansion is better than AL. Malleability too.
i have seen soft copper used in piping lpg gas from the big tanks to the house......you know, the tanks that folks outside the city limit uses, since there is no gas service that far out in the country?
now wether that makes a diff. between lpg and ng, i have no clue on that