New AC System Question
Always replace refrigerant lines when changing refrigerants. You can never get all the oil out of the piping system. Oil will still contain the old gas & can contaminate the new system. Also, not all oils are compatible. Even if I'm only replacing the old unit with a new one (an R-22 system for an R-22 system) I still recommend replacing the line set. It's better for the new unit. Find out if the contractor is installing an R-410 system. R-410 runs at much higher pressures than R-22. You may want to replace the line set just to be sure of the integrity of the copper. (Depending on the age of the old unit). Make sure warranties are covered if you don't replace the line set.
Last edited by Atlas; 09-22-2008 at 07:40 PM.