This biological growth may migrate into the condensate drain line or the drain trap and form a blockage.
Drain pipe hvac condensate drain line design.
Just pour a cup of bleach in the drain line s access opening near the indoor air conditioning unit.
Three quarters of an inch is sufficient for up to 20 tons according to the imc unless the drain outlet size is larger than in ch use t able 307 2 2 for condensate pipe sizing.
If the condensate drain line is clogged you will need to use a wet dry vacuum or a special pump to unclog the line.
This will kill any algae mold or mildew that has formed in the pipe.
Plumbing code citation for installation of air conditioning condensate drain piping.
Drain s 2015 imc 307 2 2 requires that an air conditioning condensate drain inside diameter should not be smaller than in ch and should not be smaller than the drain pan outlet diameter.
Condensate switches imc 307 2 3 states that all hvac equipment that produces condensate must have either a secondary drain line or a condensate overflow switch a secondary drain pan with a secondary drain line or condensate switch or some combination of these installations should be used to prevent overflow if the primary drain line blocks.