What a day already. Jump in the shower at 0540 and NO hot water. Cold Shower. 0600 in the crawl space and troubleshooting the problem. 0600-0730 replacing hot water supply lines in anticipation of a sediment blockage somewhere. 0735 realized that the "this guy" never winterized the outside hose bib,therefore freezing the hose and ultimately bursting the hose. The tee for the hose bib line is just upstream of the water heater inlet, which caused a drop in pressure to the water heater. So, the lack of water pressure in, caused a drop water pressure out of the water heater. Closed valve to hose bib on supply line, pressure restored through water heater, and thus a restoration of hot water.
0810 first cup of coffee. What a day already.