Stormin Mormon wrote:
During the phase change from liquid water to solid ice, the
water (ice) expands. It can easily crack the pipe. So that
when the weather warms up, the drain trap leaks.


I don't believe it can crack the pipe.

As the water turns to ice it expands, true. But in a p-trap it's got PLENTY
of space to expand into (like millions of cubic feet) - in both directions.