Can supercooled running water freeze due to a pressure change? Thursday I spent almost all day prepping for our "Arctic blast" that rolled in late in the afternoon. (Most impressive!) Among many other things, I checked to make sure the small thermostatically controlled heating element under our water tank was plugged in. (The wellhouse is part of but outside our house proper.) I ended up getting to sleep around 2 am -- exhausted & filthy I just crashed out on the carpet in the LR. (With all my warm clothes on it was quite comfy.) I woke up ~8 am:...