I have a sink near to the hot water tank, that almost instantly, the hot water comes on and with great pressure. Now when I go upstairs to the kitchen, I have to run the water to get hot water, the same for upstairs bathroom, only the bathroom gets hotter faster than the kitchen. Theories?
Water is heated at the bottom of the tank. As you need hot water the stored hot water at the top of the tank will be released 1st. Cold make up water is then added thru the cold water side, down the dip tube to the bottom of the tank to be heated again. The temperature / pressure relief valve protects the appliance should too much pressure or temp occur. Your hot water has to travel along the distance of the pipes to reach the fixture. Low cost insulation can be added to help.