vent pipe in expansion tank Home › Forums › Public Forums › General Plumbing › vent pipe in expansion tank This topic has 1 reply, 2 voices, and was last updated 22 years, 1 month ago by Wallingford Plm+Htg. Viewing 1 reply thread Author Posts 2 Feb 2001 at 1:46 pm #274560 MasterPlumbersKeymaster can somebody please tell me why the vent pipe over my expansion tank is continually dribbling hot water? It seems to have just started doing this. 2 Feb 2001 at 11:10 pm #289954 Wallingford Plm+HtgParticipant Automatic air vents should be replaced every 2-3 years. Author Posts Viewing 1 reply thread You must be logged in to reply to this topic. Log In Username: Password: Keep me signed in Log In