Condensation line freezing in NC, codes and recommendations ?
I live in North Carolina. We purchased a new construction home. The furnace is a 90% efficiency Lennox. When the nights get too cold, the 3/4" condensation line freezes and (I am told) that the lack of the furnace being able to sense a vacuum in the line, will not let the burner ignite (it is a gas furnace). I saw other postings stating what the code is for NJ .... but what is the code for NC ? Also what are the recommended solutions ? It seems that I could insulate the pipe and when it gets close to the ceiling on the slope, remove the insulation from the ceiling and run it up and over the pipe so that it can take advantage of the ceiling heat. The drain line run is about 30' and then down 9' wall to the outside. Can I just wrap the drain line with heat tape ? The water line heater that I see at ACE hardware indicates on the package "for water lines only... not for use on drain lines"... not sure why. Surely there is a recommended procedure / solution... the development that this house is in has this problem in multiple homes but I want to make sure the H&AC folks fix it correctly and not by the cheapest means. Again, not sure what the NC code is.
Many thanks,
Craig