Adam Preble wrote:

I'm trying to get more information about what I might be seeing here. I
have a home warranty that will probably get it repaired, but I wanted to
make sure they sent the right guy out (plumber or water heater repairman).

When I'm running hot water in the kitchen, I'm getting a Continual
pounding sound from the water heater. I think it's like water hammer,
but it's at a rate like a woodpecker attacking a tree in a cartoon.

It's happened when running the sink on hot or the dishwasher. Any ideas?

If it's a gas-fired heater and the hammer only occurs when the
flame is on, then it is caused by heavy sediment buildup in the
bottom of the tank. The water boils at the bottom and small
bubbles "explode" into steam.

You will probably get the "Oh, that's normal..."
and, in a sense it is.

There might be other causes for the noise, but that's one.

Jim