Good Afternoon, I live in a 2 story home and discovered this morning that I have HW on all levels of my 2 story home (basement bath, main level kitchen and PR), but not the 2 baths on the second floor. There is no apparent leak and no water flow when the faucets are turned to hot water. Any obvious things I should do or look for? I very nervous about having a pipe eventually burst (especially during the night).