Atwood Hot water heater drain plug
Hello, My 5th wheel has an Atwood hot water heater that came with a nylon (plastic) drain plug. The location of the plug makes it very difficult to get a wrench or anything on it to remove the plug...
Forum Discussion
The reason Atwood uses nylon plugs is because the threads of the tank drain hole are aluminum. If you're not careful what you're doing you can easily damaged the threads when screwing in any metal fittings. Since this is something that has to be removed frequently Atwood provided plastic plugs as well as the ability to get plastic replacement plugs.
As previously noted, the overpressure temperature relief valve is bronze. Also the gas control valve is non aluminum and it screws into a hole in the side of the tank. It also has a copper probe that inserts into the tank. A little bit of Teflon tape is not going to do anything to electrically isolate any of these fittings from the threads in the tank. Although galvanic corrosion can occur between different metals, it occurs to different degrees with different metals when reacting with aluminum, steel being the worst with Brass and bronze at a lower degree. If Atwood was really worried about corrosion between the bronze relief valve and aluminum tank they would have provided something different than a sacrificial inner lining.
As previously noted, the overpressure temperature relief valve is bronze. Also the gas control valve is non aluminum and it screws into a hole in the side of the tank. It also has a copper probe that inserts into the tank. A little bit of Teflon tape is not going to do anything to electrically isolate any of these fittings from the threads in the tank. Although galvanic corrosion can occur between different metals, it occurs to different degrees with different metals when reacting with aluminum, steel being the worst with Brass and bronze at a lower degree. If Atwood was really worried about corrosion between the bronze relief valve and aluminum tank they would have provided something different than a sacrificial inner lining.
