Re: What did you do to your coach today.
Reply #130 –
YES, there will be corrosion. Brass is a much more noble metal than aluminum (Atwood tank an aluminum alloy). That is why Atwood only uses/sells nylon drain plugs-- about $1 each.
YES, the aluminum threads will serve as the anode, sacrificing themselves to protect the more noble brass. How fast? LOTS of variables-- hardness/mineral content of water, number of heat cycles the heater is used (more reactive when hot than cold), tank stored dry/wet, etc.
Will it affect the longevity of the water heater? No hard and fast rule, see above paragraph.
I only use the Atwood nylon drain plug. Were I to want to install a permanent drain, I would use a non-conductive adapter to isolate the metals.
Brett