Atwood WH tank failed, no parts available, now what?

[ElCaminomanT]

The Atwood GCH10A-4E in our 05 Vectra 40AD failed this weekend due to internal corrosion of the tank. It appears there are no longer replacement tanks (91028) available for this heater, or even complete heater units! Since Winnebago installed the unit below the floor in the battery compartment behind a compartment door that specifically fits the location of the Atwood exhaust flue, I’m not sure what to do now. Suggestions??

[Oldchinahand]

We run the same heater and keep a close eye on ours. We love the heat exchanger feature. Heat anytime the engine is running. Electric in a park. Gas in the boondocks.

The GC10A-10E (w/o heat exchanger) is a slide in replacement. Listed in several places. Seem to be OOS. Not mfg'd anymore?

We are constantly monitoring RV dismantlers. Not a lot of hope. The Furrion Rv Tankless WH #FR98SR has been recommended to us by several sources including ETrailer as a slide in replacement. Gas only. Grrrrrrr!

We've had tankless in three sticks n bricks. Not impressed.

Fair Winds and Following Seas

[creativepart]

Visone says they have used ones.

https://usedrvparts.visonerv.com/cgi...rheaters.s2.pl

[ElCaminomanT]

Originally Posted by creativepart

Visone says they have used ones.

https://usedrvparts.visonerv.com/cgi...rheaters.s2.pl

I'll be calling in the morning! Thanks!

[ElCaminomanT]

Originally Posted by Oldchinahand

We run the same heater and keep a close eye on ours. We love the heat exchanger feature. Heat anytime the engine is running. Electric in a park. Gas in the boondocks.

The GC10A-10E (w/o heat exchanger) is a slide in replacement. Listed in several places. Seem to be OOS. Not mfg'd anymore?

We are constantly monitoring RV dismantlers. Not a lot of hope. The Furrion Rv Tankless WH #FR98SR has been recommended to us by several sources including ETrailer as a slide in replacement. Gas only. Grrrrrrr!

We've had tankless in three sticks n bricks. Not impressed.

Fair Winds and Following Seas

The reasons you mention are why we really like this WH, it is so versatile! If it comes down to it, the non-heat exchanger equipped version will be what gets installed instead but I want to exhaust all options first.

I'm also not a fan of the tankless systems at this time. I do hope they will get better with time.

[Ray,IN]

IF the leak is not the result of freezing damage, there is a good chance it may be welded/patched using TIG welder - and someone who know how to use one.
If corrosion is the cause, scrap the unit.

Visonerv.com has expensive pricing, about the same a new, but if there is no other source___.

[Oldchinahand]

Thanks for the lead Creativepart. Since John & Gina are in extremis, will give them a few days to order, then call myself. Maybe they have two or a call list.

Barring catastrophe, we are not likely to retire Miss Winnie 'til we can't climb those five steps.

So we've got a spot on a high shelf in the garage for a spare w/h.

Fair Winds and Following Seas

[Oldchinahand]

Let me add one additional thought. We bought our rig new to us when it was only a couple of years old. Among other things, we immediately installed a magnesium annode in the W/H

Well aware that's controversial. I pontificated my views, including galvanic charts some time back. Atwood advertised their aluminum lining as being the annode. True. But as soon as a pin hole in that lining corrodes through, galvanic differential accelerates.

This old sailor is of the opinion that the reason our 15 year old Atwood lining looks (borascope) so preserved, is that magnesium annode changed every six months.

Fair Winds and Following Seas

[Ray,IN]

Originally Posted by Oldchinahand

Let me add one additional thought. We bought our rig new to us when it was only a couple of years old. Among other things, we immediately installed a magnesium annode in the W/H

Well aware that's controversial. I pontificated my views, including galvanic charts some time back. Atwood advertised their aluminum lining as being the annode. True. But as soon as a pin hole in that lining corrodes through, galvanic differential accelerates.

This old sailor is of the opinion that the reason our 15 year old Atwood lining looks (borascope) so preserved, is that magnesium annode changed every six months.

Fair Winds and Following Seas

Atwood has an aluminum tank, no anode rod. .Aluminum and magnesium are both on the same end of the galvanic scale.
In addition, fresh water and salt water create much different reactions.

[Oldchinahand]

Still controversial, I see.

And truisms in your response 1Sgt.

Both are on the same end of the galvanic scale, with magnesium more reactive. Aluminum, zinc and magnesium are all tried and true anodes. And, salt water is very conductive and facilitates galvanic action more so than fresh. With distilled water having extremely low conductivity.

However, hard water abounds throughout our travels. Hard water, plus 120F+, plus the normal precipitate we all flush out water heaters to remove, are mitigators.

To paraphrase Jeremiah, I know not what path others may tread, but me and mine........

Travel season for us begins soon. Grist for the campfire over tall gins and short tonics.

Fair Winds and Following Seas

[Oldchinahand]

Should have added it to my other response to you. Shame on me. That TIG tip is helpful. Just happen to have one.

[ElCaminomanT]

I'm waiting to hear back from Visone. Their pricing seems fair, if they have one to send me. IF I could find a new one one they all show for more than double what the used one would cost. Don't have much option at this point.

I borescoped the tank through the drain and there will be NO attempting to repair my existing tank. The hole is on the cold water inlet bung but the inside of the tank is in very rough shape. We've owned the big girl since Jan 2019, who knows how many gallons have run through that tank in the 17 years it's been in service.

[MadMaxWinny]

Just worthless info (among sailors):

Magnesium anode = Fresh Water
Aluminum anode = "Brackish" Water
Zinc = Salt Water

Choosing the wrong anode can be very unfortunate in galvanic corrosion environments. Where does the potential AC current come from? 120v stray from the shore power to the heater?

[Oldchinahand]

Well, there's a whole new direction, MadMax. Haven't given that much thought. But at first blush, there is tons of AC and DC wiring proximate to the W/H for induced current potential. The gas phase is electric start, then there's the electric phase dip heater, and the GCH10A-4E (H for heat exchanger) has engine coolant circulating constantly through the exchanger when the engine is running. Moving liquid (or gas) has induction potential. Whatever, that magnesium anode sacrifices itself pretty quickly, and, knock on wood, the aluminum inner tank lining boroscopes in good shape so far.

Maybe these big old boats would be well served with degaussing cables?

More Grist for the Campfire.

Fair Winds and Following Seas

[MadMaxWinny]

I'm wondering if a galvanic isolator might help. An isolation transformer sounds like expensive overkill (even hard to justify on a smaller boat). It did not immediately occur to me that motorhomes would have such an issue, but with large inverters, chargers and gensets using either a floating green ground or a frame-ground, I'm starting to see the "light."

[jerichorick]

Originally Posted by ElCaminomanT

The Atwood GCH10A-4E in our 05 Vectra 40AD failed this weekend due to internal corrosion of the tank. It appears there are no longer replacement tanks (91028) available for this heater, or even complete heater units! Since Winnebago installed the unit below the floor in the battery compartment behind a compartment door that specifically fits the location of the Atwood exhaust flue, I’m not sure what to do now. Suggestions??

Check this out: https://www.adventurerv.net/atwood-g...s0a8ps2qivb8b7

[Ray,IN]

Originally Posted by MadMaxWinny

Just worthless info (among sailors):

Magnesium anode = Fresh Water
Aluminum anode = "Brackish" Water
Zinc = Salt Water

Choosing the wrong anode can be very unfortunate in galvanic corrosion environments. Where does the potential AC current come from? 120v stray from the shore power to the heater?

There is no "stray" outside voltage. The potential difference is what creates the low voltage. As oldchinahand said, when the same metals are in distilled water there is no/very little to conduct the potential low voltage.

reference: https://www.engineeringtoolbox.com/e...ial-d_482.html
and: https://byjus.com/chemistry/galvanic-corrosion/

[Oldchinahand]

Thanks jerichorick, bookmarked that site for reference. Not the heat exchange model, but beggars can't be choosers. Costs almost as much as that new kitchen faucet SWMBO made me put in.

AND

In the "related items" column and the "also purchased with" column we find the "Water Heater Anode Rod, Atwood".

Fair Winds and Following Seas

[ElCaminomanT]

Originally Posted by creativepart

Visone says they have used ones.

https://usedrvparts.visonerv.com/cgi...rheaters.s2.pl

Visone got back to me and unfortunately this one is already gone. He said this particular unit is in very high demand, gee I wonder why? He said to check back once or twice a week as they continually get fresh vehicles in and another will become available.

[Oldchinahand]

That's what they told me too, John. Figured you got it.

The search continues. Really like the motoraid feature. Free hot water on arrival, and free hot water on the road when we drop the lunch hook.

Good hunting.

Fair Winds and Following Seas