Water Heater Rescue: Know-How, Troubleshooting, Anodes graphic

Tanklets > Sediment Control Issues


Q: Dear Larry, you've mentioned in a couple of posts here that you like Mag-Erad, but then also that you don't like the concept of heating water in a heater that isn't completely full. Seems like a Catch-22, when one reads the Mag-Erad instructions. Any way to square the circle? What is the stress engendered by this form of heating, exactly? The tank is being watched and it's for a short time so it can't be the fact that the T&P valve is not submerged. Fumes at 212 being hotter than water at 130? Any diasters you've seen during this maneuver? Do you sell a Muck-Evac?

A: The problem with heating any fuel fired tank that isn't full of water is that the uncovered part of the flue must get quite hot as water can't keep it cool. From there you get thermal expansion of the steel flue, creating stresses in the tank.  You might also damage the lining, particularly if water does touch the hot surfaces. 

Letting the Mag Erad work longer could help.  Adding a little preheated water could help.  I've never seen any disasters using this product, but then I avoid disasters in my work :cool:

I no longer make the Muck Vac, but anyone with a mechanical bent is welcome to give it a try. -- Larry (1/24/13)

Chemical Sediment Dissolver

Q: Where can I get a sediment dissolver for my water heater? I opened the drain valve and water drips out very slowly.

A: The only one I'm even slightly familiar with is called Mag-Erad. See if you can order it through a local hardware store. (1995-2000)

Water Heater Noises

Q: I did what Water Heater Rescue told me to do, except for changing the dip tube. Still have the sound. I've had trouble getting the dip tube from the local plumbing market, plus medical problems caused me to delay any further repairs. I will do anything and everything before I tap those water heater legs with a hammer (like putting your finger on your head and spinning around ten times). Water Heater Rescue was real helpful. I just haven't been able to follow up on their recommendation.

A: The sad fact is, flushing your water heater may not completely get rid of the noise. A flush will likely leave a little sediment, and it doesn't take much to make noise. However, it will come closer than anything else. The one thing you didn't do is the thing you need to do. With a curved dip tube and ball valve drain assembly, you can flush most of the sediment out and keep it under control. Without the curved dip tube, you'll get the sediment just in front of the drain valve.

Without the ball valve, odds are the cheap plastic affair that comes with the tank will either clog or not stop leaking afterward. Needless to say, tapping on the legs won't do anything except make your water heater say "ouch." Oh, and you can buy those items as a kit from me -- and it's unlikely you'll find a curved dip tube anywhere else. Practically speaking, they don't exist. I bend my own over a Coleman stove.... (1995-2000)

Q: Hello, I have tried various BBs on the Web and received no answer to my question, so I thought I'd try you directly, hope you don't mind. I recently purchased a home which included a State Censible 510E. This is a 75-gallon and about 10 years old. It heats water very well, doesn't leak, overall performance is fine. However, when it runs, there is a loud banging noise, so loud that you can hear it from the opposite side of the house, it sounds like someone's knocking on the door. What causes this? The previous owner told me that "a baffle had been removed" but was not specific. I have a one-year-home warranty, should I have this water heater replaced? Thanks in advance for any advice.

A: Hard to say without hearing the noise. A 10-year-old heater probably has enough sediment in the bottom of it to make sediment noise. That usually is a rumbling, snap, crackle, pop sound that can be very loud and disconcerting if you don't know what it is. There could be a lot of sediment or only a little. It doesn't take much to make noise, and State often uses aluminum anodes, which slough off as they corrode and add to the gunk on the bottom of the tank and increase the noise level. The noise doesn't mean the tank is bad. But a 75-gallon tank usually has 1-inch plumbing. That's too big to put in the flush system I sell on my site.

You might be able to find someone in your area who has a Muck-Vac water heater vacuum who could come and clean the tank out. Another possibility: If it's a rattling, it could be heat traps in the nipples, which could be removed. If the noise doesn't resemble either of these, I'm less certain. The only baffle a water heater has is in the flue and removing it wouldn't cause noise like you describe. It exists to slow down the flow of hot air and get better energy efficiency. Someday you may be able to record the sound, encode it in a file, and send it to me as an e-mail attachment. But until that day, this is the best I can do. (1995-2000)

White Deposits in Shower Heads and Aerators

Q: Your hot water heater rescue Web page is very informative. My girlfriend has an almost 4-year-old townhouse. The faucets and shower head screens are clogging with small white mineral deposits. Looks and crushes like little pieces of limestone just big enough to clog the pin-hole size screen in faucets and shower head.

I have determined it's not from cold water side but hot water. I drained water heater (typical 40-50 gal gas) and refilled, but problem continues. My theory is mineral scale buildup in water heater. Does this seem correct? Why is this occurring? She has city water, and how can this be solved? Any help would be greatly appreciated.

A: If you have a recirculation line, it might be calcium carbonate. Otherwise, it's much more likely to be bits of aluminum from the anode rod. We had a problem a month or two ago with a client whose laundry-room washing machines were getting their filters clogged with white gunk. It was from an aluminum anode.

So the question now is, do you have a recirc line or not? In case you're unfamiliar with the term, it is a pipe, perhaps 1/2-inch diameter, that runs from the farthest point of your plumbing back to the tank to ensure that when you turn on the hot water, you get it quickly instead of having to wait for it to flow from the water heater to the faucet. If there is one, it will enter the tank at the bottom. As for the anode, first, what brand of heater do you have? Second, is a hex-head anode exposed on top? Third, if it is, does it have a bump on it?

Q1: No, there is no recirculation line. But the anode rod may be the problem. As to what brand and how it is attached, I will have to visit and look. I understand the purpose of the anode rod (to prevent rust by sacrificing itself), however would it cause white particles in hot water? Is this something that can be replaced without replacing the whole hot water heater?

A1: OK. That simplifies things. It's almost certainly an aluminum anode rod and it's almost certainly causing your problem. Calcium carbonate does build up in the bottom of water heaters, but unless there's a recirc line, once it settles to the bottom, it stays there. You don't have to replace the whole tank, just the anode.

You are correct that the anode is there to sacrifice itself to protect the tank from rusting. Anodes are either aluminum or magnesium. Some makers believe that aluminum will be consumed a little more slowly in certain types of water. It's one notch down on the scale of reactivity from magnesium. In our opinion, that simply means it doesn't protect the tank as well.

However, your problem has to do with another property of aluminum: as it corrodes, it sort of "sheds." Bits of it fall off and flow out the hot water port, causing your problem. Other bits break off and fall into the bottom of the tank. Gunk in the tank bottom eventually causes popping and rumbling noises, which can be annoying if the tank is inside your living space.

Tanks with aluminum rods can make a whale of a lot more noise than those with magnesium ones because the latter sticks to the rod until it's completely eaten up. You'll need to figure out where the anode is. Your tank may have an exposed hex-head anode. It might have a hex-head anode hidden under the sheetmetal top.

Or it might have what's known as a combo rod as part of the hot-water outlet. It might be best to hire a plumber to track it down and take it out. Sometimes they're very hard to extract. We can sell you a magnesium anode if you can't find one locally. (A disintegrating dip tube can also cause this problem.) (1995-2000)