Corrosion around top of water heater?

bipbap

Merry Xmas everyone!

Just noticed that one of our gas hot water heaters has corrosion around the top while the other one doesn’t.

Any idea what would cause this?

Larry Weingarten

Hi, There is a slow leak someplace. but not coming down from the vent. You can see water has come from a small hole through the top towards the camera also. The best check is fittings. If it isn't at the fittings, it must be through the tank. If there is no evidence of leaks from the visible plumbing, I'd check what's under the top by cutting the top back in a pie shaped sort of way and folding those pie pieces down into the foam. With that heater it must be hot, cold, or anode. Knowing the age of the tank and whether the anode has been changed would be good background info to have.

Yours, Larry

bipbap

The anode has not been changed and they were both installed new around Sept 2016 so about 8 years old. Is that helpful?

Bob Harper

You also have improper venting that is causing some degree of backdrafting and condensation of flue gases. The vent connector, though upsized as it should be, is either level or possibly running downhill a bit. It must slope up towards the chimney 1/4" per lineal foot. See the darkened areas around the draft hoods? They should be pristine. Some of the corrosion could be from acidic flue gas condensate.

What is the chimney/ vent and is anything else attached? What diameter, total BTU inputs, and lateral offset?

Larry Weingarten

Hi, I'd pull the anode and see if there is anything left. They should be replaced when six inches of the core wire is exposed. If there is little or no sacrificial metal left, the tank has been rusting. Do you have any info on the water quality? Oversoftening can completely use up an anode in six months.

Yours, Larry

ps. If you are messing with the anode, do get one for the other tank!

Dennis

The tank is toast, change it before it springs a damaging leak. Next time around install a permanent DC anode rod.

bipbap

How do I pull the anode to check? Is this something a non-super handy guy can do?

hot_rod

Any moisture below the tank, or hissing on the burner?

Larry Weingarten

Hi, The anode needs a 1-1/16" socket… best use a six point for a good fit. Use a strong breaker bar and have a cheater pipe on hand for more leverage. Leave tank mostly full of water to help hold it in place. I like to use a small sledge on the breaker, while pushing pretty hard. This breaks it loose. A 3/4" drive is best as I've broken 1/2" drives, but most will come out with the 1/2".
Yours, Larry

bipbap

Hot Rod, No hissing or water anywhere

hot_rod

I'd be shopping for a new tank, an anode rod may not be the fix. How old is the tank?

bipbap

Both were installed Sept 2016

I don’t think I’m handy enough to handle those anode checking instructions posted….

hot_rod

The wholesalers that visit here claim 7 years is a good run for todays tank style heaters.

pecmsg

https://forum.heatinghelp.com/discussion/comment/1830325#Comment_1830325

When you get it replaced remove the anode rod and never seize the threads and reassemble. It makes checking and replacing much much easier.

jesmed1

And get yourself a cheap corded impact wrench for the initial removal. Otherwise you will need a 4-foot length of pipe slipped over the handle of a 1/2" breaker bar to get that thing out.