On Mon, 7 Sep 2015 04:42:27 -0700 (PDT), trader_4
wrote:


Sounds like something is not right.
What is frost line there? Hard to believe
P trap freezes if every thing is done right.

RV/non-toxic antifreeze would be one solution.

+1

OP could search for winterizing his home during a hard winter vacancy.
Plenty of information out there.