Can an old water heater cause iron stains on fixtures?

[TJanak]

I bought this house three years ago with a well with moderate hardness and iron. Electric HWH is who knows how old. (Mor-Flo Ind. S/N 704946, I thought someone said the serial number tells the mfg. date?) At the time the water softener was barely removing hardness and probably no iron. Put in a new softener last summer and water is noticeably better and tests good. Around the same time we put in new white Glenwall toilets, white cast iron tub, and white porcelain pedestal sink. The tub and sink, along with the dishwasher have iron staining after a while of use, several weeks. The toilets and clothes washer do not have the iron stains.

To me, the obvious difference is the fixtures using hot water have the stains and those using only cold water do not. Could there be a build up of iron in the HWH from years of use, or possibly internal rusting of the HWH tank causing the fixture staining with the hot water? I'm willing to just replace the heater and give it a try, it looks old as heck anyways. Does my theory sound plausible?

[jadnashua]

Get a bucket and run some water out of the drain of the WH and see what it looks like. Also keep in mind that if any piping in the house is galvanized iron, as it ages, it will rust as well. These were somewhat common on pipe nipples for tub spouts, and could be anywhere in the house including the main supply piping. Hot will possibly cause it to rust quicker than on the cold. If you had significant rust from inside of the WH, it would probably be leaking by now.

[TJanak]

Thanks for the reply Jim.

I do need to try and drain the WH but have not had the time. Also, by the looks of the drain it will probably leak after I mess with it because it has been closed for probably 15 years so I'm hesitant to jack with it. My plumber said they often have a hard time getting them to drain when they replace them because they are plugged up with rust/crap in the bottom of the tank. He told me to leave it alone.

All of the galvanized nipples have been replaced with brass when all of the new fixtures were installed. Supply piping is all copper except for about a foot on the inlet and outlet of the WH that is old galvanized and I would change with a new WH to brass. Also the drop pipe in the well is galvanized.

Other than the ~2' of galvanized at the WH there is nothing that explains to me the staining with hot water, and I don't believe 2' of pipe is causing this.

[jadnashua]

You might be surprised...old pipes can release a lot of rust when they start to go. Also, at 15-years, the WH could be on borrowed time, so if it really bothers you, you might consider just replacing it along with the remaining galvanized piping. Also, consider that it isn't too hard to cut those pieces of piping out and slap in a couple of flexible copper supply lines. WHen you do have the WH replaced, consider having them take out the (normally crap) drain valve and replace with a full-port ball valve...much easier to drain and if required, you can stick a wire or rod through to break up the sediment.

[ballvalve]

Yes, the only way to clean it out is to remove the plastic drain, and be ready to "dig" it out - and flush water through the inlet while rodding it though the drain.

Check the anode rod - if its shot, T-value is selling 40 gallon water heaters for $199 bucks this week. Cheaper than the hideous big-boxes.

[Terry]

Any water heater over ten years old is living on borrowed time.
If you have rust on the hot side, that normally indicates that the tank is already rusting out. Changing the anode rod doesn't repair the damage already done to the tank. If you weren't seeing rust, then maybe I could see worrying about the anode rod. It looks too late for that though.

The big question is; where is the heater located? What damage can occur when if finally gives out and starts gushing water?
Do you have carpets? Or is it in the garage?

Most townhome and condo associations around here require replacement at ten years to prevent catastrophic damage to units below them.
They figure it's cheaper to keep ahead of the repairs rather then clean up afterwards and deal with insurance and the $1,000 deductibles.
During some repairs, it can force homeowners to relocate while the reconstruction takes place.

[TJanak]

Thanks Terry. The water heater is in the garage but backs up against the kitchen wall and is on the same level of slab so water damage is a concern.

The UL tag on the heater says 1981 on it. Could it really be 30 yrs old?

The local supply house I use has A.O. Smith 52 gal. and quoted me slightly less than the big box price. I would use the local guys even if they were a little more. Is A O Smith decent?

I figured on putting a pan under it as the current heater has no pan. I assume I'll need to run the drain out the exterior wall but what about the T&P valve? Is it normally piped down into the pan or something?

Thanks

[Terry]

A.O. Smith Corporation uses a 10-digit serial number with a letter-month/year code in the second third and fourth digits of the serial number. The letters A to M, excluding the letter I, are used to designate the months 1 to 12 followed by the two digit year. For example,*H06****** would indicate that the water heater was manufactured in August 2006.

The relief doesn't run to the pan, as that wouldn't be quick enough to drain it. It normally runs and terminates above a drain or to the outside. Either way, it should be visible.