Anode Rod

[onemilmhz]

All the water heater talk had me out inspecting mine today. I've never changed out an anode before. Is this typical of a worn rod? A good deal of white sediment came shooting out when I drained it. Also, how can I determine what type it is, magnesium or aluminum?

[NRALIFR]

Wishbone51 wrote:

NRALIFR wrote:
Oh, and BTW..........guess what those aluminum boat owners use to prevent their expensive boats from corroding? Magnesium anodes!

Hahaha.. Where do they put the anode? dangling in the water? 🙂

Yes. Screwed to the hull below the waterline.

:):)

[Wishbone51]

NRALIFR wrote:
Oh, and BTW..........guess what those aluminum boat owners use to prevent their expensive boats from corroding? Magnesium anodes!

Hahaha.. Where do they put the anode? dangling in the water? 🙂

[NRALIFR]

"Atwood uses an aluminum tank. Aluminum doesn't corrode, so in theory there's no reason to use an anode. But they use a steel threaded insert for the drain, which is in turn welded to the aluminum tank. Guess where my last two elderly (>10 years old) Atwood heaters developed a leak? I don't know if an anode would have protected the weld or not."

Well, this is another case of "I read it on the internet so it must be true" myths.

Aluminum most certainly does corrode, just ask any aluminum boat owner. And, the threaded insert for the drain is not steel. I just tried to stick a magnet to the drain on mine, and it doesn't stick.

The reason Atwood says you don't need an anode on their tanks is because the aluminum TANK ITSELF IS THE ANODE. They even say this in their water heater literature, and warn that the tank MAY develop pin holes over time, depending on the type of water you have.

Oh, and BTW..........guess what those aluminum boat owners use to prevent their expensive boats from corroding? Magnesium anodes!

:):)

[Old-Biscuit]

Atwood water heaters tanks are made of aluminum alloy........no steel parts/components. Drain hole is aluminum that is why the nylon drain plug is used (so threads are not damaged/galled up)

No anode cause of the use of aluminum alloy tank...........although given enough time the tank can develop pin holes due to water chemistry/electrolysis.
Just like using an aluminum anode rod.

[2oldman]

Wishbone51 wrote:
.. Atwood.. "No anode required" .. what they do different to not require an anode? Maybe a better coating?

From rvforum.net:

Suburban uses glass enamel over a steel tank. If the enamel was applied perfectly and stays in perfect condition, water never contacts the steel and all is good. But any pinhole exposes the steel to water, so the anode is needed for protection.

Atwood uses an aluminum tank. Aluminum doesn't corrode, so in theory there's no reason to use an anode. But they use a steel threaded insert for the drain, which is in turn welded to the aluminum tank. Guess where my last two elderly (>10 years old) Atwood heaters developed a leak? I don't know if an anode would have protected the weld or not.

[Wishbone51]

I saw an Atwood at an RV store today, and there was a sign on the box that said "No anode required" .. Do you know what they do different to not require an anode? Maybe a better coating?

[Old-Biscuit]

ernie1 wrote:
Old Biscuit: Do your residential water heaters only last 6 or 7 years? Man! My water heaters always last 15-20 years. Hmmmm, must be the water.

No the cheaper ones that have those 3-6 yr warranties

Mine last about 10 yrs even with good anode rod and bottom flushing. Hard water.

[ernie1]

Old Biscuit: Do your residential water heaters only last 6 or 7 years? Man! My water heaters always last 15-20 years. Hmmmm, must be the water.

[Old-Biscuit]

SoundGuy wrote:

Old-Biscuit wrote:
The idea is for the rod to be 'sacrificial' vs the steel tank of water heater.

Sacrificial yes, but the anode rod is not protecting the steel tank per se as that tank is lined with porcelain ... rather, in Suburban's words the purpose of using an anode rod in one of their water heater tanks is because "Heated water attacks all metals, but not porcelain. That's why Suburban uses a porcelain-lined, steel water heater tank with an anode rod to "absorb" the electrolytical action".

And w/o that sacrificial anode rod those Suburban porcelain-line STEEL tanks with rust/deteriorate/leak rather quickly.
If the porcelain lining didn't have hairline cracks, weak spots, incomplete coverage if would fully protect the STEEL tank......but it doesn't hence the need for the sacrificial anode rod. Simple chemistry at work.

[SoundGuy]

Old-Biscuit wrote:
The idea is for the rod to be 'sacrificial' vs the steel tank of water heater.

Sacrificial yes, but the anode rod is not protecting the steel tank per se as that tank is lined with porcelain ... rather, in Suburban's words the purpose of using an anode rod in one of their water heater tanks is because "Heated water attacks all metals, but not porcelain. That's why Suburban uses a porcelain-lined, steel water heater tank with an anode rod to "absorb" the electrolytical action".

[Old-Biscuit]

Typically the anode rod will last about 6-7 yrs. in a residential WH.

Most WH's will need replaced by then anyway :B

I find them at Home Depot/Lowes.
Small market cause many folks don't know about them or forget about them. So store space goes to other items.
If not in store...easy to shop on-line and have 'shipped to store' for free.

Heck Sears even sells anode plates etc. for boat rudders and prop shafts

[ernie1]

Forgot to say that changing the anode is very easy. They unscrew from the top of the water heater. The anodes are not always easy to find for residential water heaters. I wonder why?

[ernie1]

I try to change the anode in my home water heater as often as necessary. The last one I changed cost me $50 (got ripped off) and then the water heater sprang a leak 6 months later. Oh well.

[TenOC]

hawkeye-08 wrote:
Wonder how many of you check and change the anode rod in your home water heater?

Not a simple task -- depending on the location of the water heater.