A mate of mine, who is building a still, mentioned that only certain classes of copper tube should be used for the condensor. He said that copper tubing comes in different classifications (colour coded) dependant on the pipe use ie. water, gas, hazardous, and some of these (ie. refridgeration) have chemicals added during manufacturing process to reduce operational issues.
Does anyone know if this is true? Isn't copper pipe just copper pipe? Or are the differnet classes just different wall thickness and pressure ratings.
Any aussie plumbers our there that can help with this questions?