If electric, it is likely one of the two heater elements is dead.
Otherwise it is likely a bad dip tube.
How old is it? If it is about 10-13 years, it may have had a defective
dip tube. A while back they replaced them free, but I don't think you can
have that done anymore. You also may have had problems with the strainers
in your faucet clogging with white stuff. Replacing the dip tube and
rinsing the heater will take care of it.
If it is older, you may wish to consider replacing it. Either of the
above fixes are not expensive however and they should buy you more time.
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
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