I have a John Wood pro series hot water tank about 13 years old. Just recently I stopped getting hot water pressure. My pipes are not frozen. I have read FAQ,s and similar problem posts. I have great cold water pressure and my release and drain valves have great pressure, shooting clean hot water from them.I did not understand the advice given for checking nipples and dipsticks. My copper lines coming out of top of tank are soldered and I would have to cut them to check for calcium or crud.I feel my heater is still good and that it's a blockage or something. I could sure use some diagrams to show some of the procedures you've suggested to others with same problem. I know I will need a new water heater soon being 13 and all, but not without exhausting possible cheap fixes. Thanks, Statman from Calgary Alberta Canada EH!!
If there aren't any unions or flexible copper lines used then, yes, you will have to cut the copper line to see what the inside of the pipes look like. Per master plumber Mark, the hot side should be the one full of buildup, thus compromising your flow. This would be at where the pipe exits the tank.
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