[fold_em83]

Hey guys, I'm new here so thanks for helping me out. My wife and I just bought our first house in November. I feel I have an above average knowledge of home maintenance and repair but this has me puzzled. My problem is that when you take a shower the hot water only lasts for 10 to 15 minutes. We have a 50 gallon water heater that appears to be relatively new. I have replaced both elements but the ones that came out of it looked fine. The thermostats were set as low as they go so I turned them up a little. Both elements are getting hot. All of the pipes are copper and they are all exposed to the basement. The shower is the farthest point from the hot water heater. I have gone to the basement while the shower is running and felt the hot water pipe supplying the shower. The entire length of the pipe is warm to the touch. The most puzzling part about all of this is that when the water in the shower runs out, the bathroom sink will also be cold but the kitchen sink, which is the closest to the hot water heater, will have very hot water. I have traced all of the pipes in the basement and I can't find anything that would be causing this. Can anybody help?