Okay, let me weigh in with my humble opinion.
First of all, I see one vote for a borken dip tube, and two votes for sediment.
And the winner is... the dip tube!
Your problem is definitely caused by a dissolved/broken dip tube. A dip tube is made of white plastic. It mounts under the cold water inlet on the heater and directs the cold water down to the bottom of the tank where it's heated by the elements. When it disintegrates you get hard white particles in the hot water lines. Here's a simple test: roll some of the white particles between your fingers. If it's calcium or sediment it will crumble; if it's white plastic from the dip tube it will not.
Perhaps all is not lost: you should flush your heater at once to get rid of as much crud as you can. Here's what the great master, Tom, has to say (in a similar thread):
Originally Posted by
speedball1
For long life and fewer troubles you should keep your heater clear of mineral build-up by flushing on a regular schedule. let me show you how. Attach a hose to the boiler drain at the bottom of the tank. With the pressure on, open the boiler drain and let it run untill the water runs clear. You will see a spurt of red,(rust) followed by white grains,(plastic, lime or calcium carbonate). In your case I suppect a bad dip tube. This shouldn't take more then a few minutes. Do this monthly to keep it clear. Now flush out your hot water lines on ALL fixtures. Now pull each aerator and clean the screens. Be sure you put them back togather the same way you took them out. Don't forget to flush it out every month. Your heater will thank you for it. If you find out that it's white plastic instead of calcium and wish to replace it yourself I can walk you through the process.
Then replace the dip tube (as Tom says, if you need help doing it we can walk you through it), and clean all the aerators. While the aerators are off, run each fixture for a while to clear out the lines before putting the aerators back. MAKE SURE YOU DO THIS AFTER THE HEATER HAS BEEN FLUSHED, or you will just draw more pieces into the line.
If this works, you won't have to replace your water heater (and you'll save a bundle of money in the process). Although water heaters have a so-called life expectancy of 8-10 years, it's not true: the secret to making your heater last longer is to flush it EVERY MONTH (not just every year, like some manufacturers recommend). And MAKE SURE you leave the cold water inlet ON while flushing, to provide the pressure necessary for a good flush.
Labman's heater has been working for about 25 years, thanks to monthly flushing; Tom's heater has been humming merrily for OVER FIFTY YEARS.
The usual rule of thumb applies: if you take good care of it, it will take good care of you.
Cheers,
Moishe
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