Double trapped condensate line....

Ok, need a little help writing this one. The condensate line has two traps. One right at the unit and the other about 15’ away at the vent stack. What are the technicals of two traps…if any?

Second part-Where the drain arm from the unit enters the trap at the vent stack (the further one), it is open like an air gap. The problem is the opening is lower than where it actually drains, so water will overflow before it actually drains. Sorry I can’t think of the proper terminology to help explain.

gap close up1.jpg


double trap1.jpg

I see no way that the condensate will ever get to the drain stack as the open gap is below the trap weir.

So that begs the question, where is the condensate actually draining to?

I would say by the lack of insulation in the attic this home has never been lived in thus the A/C unit has never operated long enough to make condensate because there would be some wet drywall if that were the case. Unless that furnace is a 90% furnace you can not connect to a vent stack no matter how many traps there are. Condensate is required to discharge to a wet trap and what you are displaying is not a wet trap or even two wet traps.

One cannot connect a dry trap to a vent stack ;):wink: you get sewer gas guys come on get real think about it

It is a brand new house. Never lived in. Not completely finished. They would find out pretty quickly with the unit running that it was not gonna work.