importance of anode rod in water heaters

[Doug Lassiter]

I'd like to understand the importance of an anode rod for hot water heaters in areas with alkaline, mineral rich water. No question that the anode rod mitigates corrosion, but it doesn't mitigate scale formation. Many water heaters die because of scale deposits, and not because of corrosion. So the question is, in areas with mineral rich water, does the anode rod really increase the lifetime of the water heater, and it it really worth replacing every five years?

No argument that in an area with mineral free or softened water, anode rod replacement is an excellent water heater preservation strategy. But if mineral scale is going to kill the water heater first, why worry about corrosion?

Ideally, I'd like a response from a plumber who has done autopsies on dead water heaters in alkaline areas.

 

[Jeff Handy]

If your water is full of minerals, the anode rod might make your water stink like rotten eggs.
I had a house with very mineral-heavy well water, and had to remove the anode rod on both new water heaters I had, during my 26 years there.

Still got plenty of years from them, at least 12 each, with no anode rods.

And BTW, the friggin’ anode rods were installed incredibly tight from the factory.

Both times I had to lay the water heaters down on their sides, and straddle it like riding a horse, while someone else with a looong wrench busted it loose from the water heater.

Definitely not set up to be inspected or changed easily!

And the solid rods were too long to be removed anyway, if somehow they could have been unscrewed while the heater was already installed.

You can get anodes that are linked in short sections like a chain, that don’t need much headroom to get them out.

 

[Jeff Handy]

Drain your heater twice a year if you have heavy minerals.

Also, most heaters now have the incoming water fed in a swirling action, so that keeps at least some of the minerals from settling to the bottom.
They go right up and out as water is being used.

And install a water softener and a whole house water filter.

 

[Doug Lassiter]

Thanks. No, my water is off of limestone, so there aren't sulfides. No rotten eggs.

And yes, I'm aware that anode rods are screwed in very tightly.

 

[Doug Lassiter]

Good point about draining. I do drain twice a year, and usually some minerals come out.

Just out of curiosity, is there some strategy for removing scale from water heaters? I vaguely remember some people suggesting an occasional flush with not-too-strong acid. Vinegar? But I don't have a recipe for any such flush. Probably use the anode rod port to do the flush, and I suspect the anode rod itself wouldn't much like the flush.

 

[Diehard]

Just saw OP's last comments and deleted what I had.

EDIT: Why not pose your questions to the Water heater manufacturers?

 

[Jeff Handy]

The pros here can advise, but I have never heard of rinsing the inside with an acid to remove scale.
Just flushing to keep it from building up.

I suppose you could drain the tank, then attach a short hose to the heater drain hose bib, and with a funnel attached you could pour in a gallon or so of generic vinegar and then a few gallons of water. Let it sit for an hour, then flush it out.
But that seems pretty unnecessary.

The pros will weigh in with the answer I’m sure.

 

[Doug Lassiter]

Just saw OP's last comments and deleted what I had.

EDIT: Why not pose your questions to the Water heater manufacturers?

Very good point. I didn't notice that there was a separate forum for that. Thanks!

 

[Diehard]

Very good point. I didn't notice that there was a separate forum for that. Thanks!

There is?

 

[Doug Lassiter]

https://www.plumbingforums.com/forums/water-heaters-and-softeners.12/

I have to assume some manufacturer is lurking there.

 

[voletl]

How about you call the water heater manufacturer directly..........................