I was having problems with my hot water system a while back. It turned out to be the $7 check valve on the bottom (cold) water connector to my hot water tank – but on to the vinegar.
Before I figured out my real problem, I also found a tank loaded with a bunch of calcium looking chunks when I replaced the anode, and thought my tank outflow might have been calcified or something (I was really guessing and out on a limb)
I put 3 gallons of white vinegar along with 3 gallons of water in my hot water tank and brought it up to temp for several hours. Of course when I bled the water lines some of the vinegar water and smell came out of the taps. It smelled like a pickle factory while I was cooking up my vinegar mixture in my hot water heater. It smelled even better when I drained the tank. :crazy-ii
I went down to Home Depot and bought a water hose to ¼” copper line fitting and some copper tubing to make a “tank washer” as described on one of the other RV sites. (Actually I told the guy at Home Depot what I was doing and he steered me toward the correct parts.)
The vinegar could not have fixed my broken valve, but the combination of the vinegar bath and the flushing with high pressure water from the little copper tube washer sure cleaned up my hot water tank.
From what I could see with my fiber optic flashlight thingie (read that as bore light
for you shooters) I had cleaned the tank down to the ceramic liner. No more white calcium stuff at all. The water smelled like vinegar until I used a baking soda solution to freshen up the smell.
If you are just wanting to clean out the sediment – it did a heck of a job on mine. With a new anode and the actual broken valve replaced, I was back in the hot water business.
I have become a firm believer in draining the hot water tank and washing it out every few trips now.