Changing Atwood water heater plug to brass

The biggest issue with using the brass plug is it's harder than aluminum and you could damage the tank threads if you're not careful. Some people worry too much that the brass can also cause galvanic corrosion with the tank. Galvanic corrosion is a problem when you have metals that are too dissimilar causing them to react with each other.

Although brass and aluminum are dissimilar metals they are closer together on the galvanic chart and should not react too badly with each other. Steel and aluminum are very far apart on the galvanic chart and will react badly with each other. This can be seen by the white chalky deposits when using stainless steel fasteners with aluminum material. Steel and aluminum are the worst.

As far as galvanic corrosion the Atwood tanks also have a bronze relief valve, a gas/temperature control valve which is made out of pot metal with a copper probe that extends into the tank and whatever the material the fittings that screw into the water inlet and water outlet of the tank are made of, so over all the brass is not going to be that harmful. The tank already has dissimilar metals threaded into it that don't cause a serious problem.

For a long time I had a brass nipple with a brass ball valve screwed into an Atwood Tank with no ill effects. Someone on The Forum had a wire braided hose screwed into the tank drain hole that had a valve on the opposite end of the hose and it seemed to work fine for them. They were able to lay the hose over the door on the water heater so the valve could drain directly to the ground.

You are best off using the plastic plugs if available but as long as you're careful getting the threads lined up brass will be okay, just don't crank down too hard when you install it.

I am considering a brass plug, as my plastic plug and delicate Alu threads are leaking, even with Teflon tape on the plastic plug

Going to follow this thread

Maybe some pipe dope on a new plastic plug ?

I do drain once a year , and would prefer for it to be removable

If you install the brass plug with the petcock, how are you going to flush the tank? You still have to remove the plug. The tank should be flushed on a regular basis to remove the deposits that settle on the bottom of the tank. Atwood installed a plastic plug for a reason, not to be cheap

Interesting discussion. Seemed like it was mostly about anode rod/plug combo, or not. The one quote, taken from the "Atwood Manual", by mobewan(?) made no reference to not using a brass plug/valve fitting, just said no need to replace an anode rod, probably because they don't have one, as far as I know. The rest of the nay sayers were the usual gaggle of "experts w/opinions".
Do what works for you. If you put the brass fitting in carefully, you'll never need to remove/replace it, and your "delicate aluminum threads" will be safe forever. :B

We just had a thread on that, where ISTR the pros said it was a bad idea due to brass and aluminum issues. It sure is a PITA getting that plastic plug in and out though.

https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/29997558/gotomsg/29997635.cfm#29997635

I replaced the plastic plug with brass fittings and a 3/8" ball valve 17 years ago for that vary reason. No problems and still working just fine. Also makes it real easy to blow the crud and sediment out of the bottom of the tank

Should work, as long as it doesn't get plugged up with scale and calcium when you go to drain it. If your water source isn't too hard, it should be fine. If it does get plugged, have a wrench handy.