Hello all,
I'm not an inspector, but an annoyed homeowner whom since having the primary drain line blown out due to overflow into the drain pan, is experiencing this same gurgling, popping noise. The worst part it is the sink is 20 feet from my bed and it is loud and waking me up at night.

After reading this thread I went to my attic and traced the line from the AC to the point where it drops into the floor where I can't see it anymore. There is no trap (at least one that looks like a normal P-trap) between the AC unit and the floor, nor is there one near the sink where it intersects the pipe on the sink side. Could I install a trap just before it intersects the pipe for the sink or would I be causing more issues? I would like to find someone in the Sugar Land (suburb of Houston) area who could do this for me if you could refer anyone.

Finally, I see that this is an "Inspectors" site, so if I'm intruding as a consumer, I apologize, and someone please tell me to buzz off! If not, I would greatly appreciate any help you can provide!

Thanks!
Nick