So I've always used a 3/8" solution line with 1/4" qds (and sometimes 1/4" lead hose). But I don't really know why. Just what I've always used through the years since I started cleaning with a TM. I assume it's to help maintain temperature, but don't really know. Anyway, I need to replace some older sections of hoses that are wearing out and just started thinking about it. Is maintaining temp the reason for doing this?