Replacing ancient Suburban water heater with new?

[urbex]

So I'm pretty sure I just caused terminal damage to my water heater...

I have a 1974 Amerigo truck camper, with a Suburban G 602, 5.7 gallon water heater. I attempted to drain/flush it, and got nary a drop when I opened the drain, but did get some water out of the safety valve on top when I opened it (water heater hasn't ever been on since I bought the camper last summer, so it wasn't hot).

I figured it was just clogged with crud, so I took a socket to the drain valve to get it off and clean it....and promptly snapped it off the drain pipe...oops. The drain pipe is also packed full of calcified stuff, so I figure it's likely safe to assume there's plenty more in the tank as well, and previous owners likely didn't maintain it well.

That said, are these things fairly standard in size? As in if I get a new Suburban 6 gallon model, it should drop in the same size hole? Or are they like the refridgerators where there are a million different sizes, and I need a specific model to retrofit this old stuff?

[urbex]

I knew of the style differences between brands, and expected to replace it with a new Suburban (bonus - they're cheaper anyways!). Extending wiring and gas lines are simple if need be, especially compared to changing the opening size.

I did take a closer look at it yesterday, and was able to easily punch a small screwdriver through the crud, which let all the water drain out. I also noticed that it didn't actually break the drain tube, but did mangle the first thread or two so that I couldn't just screw a new fitting on. The tube appears to have a pretty thick wall compared to typical plumbing pipe, and I'm thinking I may be able to run a pipe tap into it and just use a NPT plug to seal it off if I can't get the threads cleaned up on the outside.

It's definitely not an anode, or the remnants of one. The drain valve on it has a rubber disc that's connected to a screw on the inside, with a hole drilled on the side of the valve. The valve screws on to the end of the drain tube, then the inner screw is run in to press the rubber disc up against the end of the drain tube. Run the screw back out, the disc retracts, and the tank water drains out of the little hole.

I looked at new anodes at the RV parts store, and there's no good way that I can see to retrofit one either.

[j-d]

YEP. Replacing Suburban (or its predecessors) with Atwood is difficult sine Suburban's oblong tank's long axis is crosswise in the coach, and Atwood's is lenthwise, so you'd have to change the square Suburban cutout in the wall to make it rectangular for Atwood. Let alone actually have space inside for the different layout. Atwood to Suburban would require reducing the size of the hole, and maybe not having the depth inside for the 90* rotation of the tank axis.

I'd like to hope that the LPG connections are similar, pre-Suburban to current Suburban. Probably wishful thinking...

[Dick_B]

Be aware of the fit and the location of connections LP and electric or you will have a bigger job replacing it.

[Old-Biscuit]

More then likely that 'calcified stuff' is the remains of the anode rod.
Anode rod material is wrapped around a steel rod that is welded to drain plug hex head.
Not the first time they have separated when trying to remove a drain plug

BUT it is a 43 year old water heater.
Time/effort not worth it.

That G602 should have a installation opening 12 3/4" H x 12 3/4" W x 20 3/4" D

New Suburban 6 gallon water heater features 12000 BTU's burner,
and is 12-11/16" H x 12-11/16" W x 19-3/16" D.
(All same size...gas only or gas/electric)

Looks like a fit.

(Atwood is completely different so no swapping brands w/o modifications----6 gallon 12 1/2" H x 16" W x 18" D)