Changing Atwood water heater plug to brass
I had to move my motorhome from it’s previous storage to a new place and the new place isn’t heated. So for the first time in 15 years I have to winterize. But since I use it during the winter I wa...
Forum Discussion
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.
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.
