hvac condensate drain hvac condensate drain zicoo000 (Mechanical) (OP) 31 Dec 13 02:44 dear engineering, can you help me with with scientific answer reference the hvac condensate drain we add to storm water or waste drain ?? RE: hvac condensate drain cvg (Civil/Environmental) 31 Dec 13 11:59 doesnt matter RE: hvac condensate drain bimr (Civil/Environmental) 31 Dec 13 15:42 The condensate should drain to the environment, but as cvg points out, since the volume is so small and the water is pure that it does not matter where it drains. RE: hvac condensate drain PEDARRIN2 (Mechanical) 2 Jan 14 07:12 It depends on the plumbing/mechanical code. If it comes from boiler flues, it could be acidic so should go to the sanitary (maybe after going through a acid neutralizing cannister which sometimes is provided by the boiler manufacturer). If it comes from cooling coils, it typically goes to either storm or sanitary, but check the code to make sure. Also check with the local code official. Sometimes they have a preference.