Thor Forums

[JDHoge]

Inspection under sink revealed that the hot and cold lines had been taped and zip tied together. Severing those connections and placing a piece of cardboard between the lines solved the problem.
IMO, the shower has the same issue (although I can't get in there to make the correction). From my work to silence the rattling of the C & H lines behind the shower wall, I know that the two are separated from the floor up. So that accounts for the rush of cold. I guess that then if you've paused for 20 seconds or more to soap up or shampoo, the tightly tethered blue and red lines under the shower have heated up enough to give you that unpleasant blast of really hot water. No solution but to disassemble (but I'm not going that far).