That's what the dude told me at the walk through when showing me about the valve to pull the antifreeze in with then he opened up the water heater access and showed the electric switch and told me to take the rod out and set it on that little ledge till I got ready to Dewinterize it.
Maybe it is just me,,, bit I would wonder what might get in there and make them self a home for the winter ??? LOL !!!
We have covers/screens over/in Everything,(BUT) I have never found a way to keep out those little (Lady Bug Looking Things)! Every Fall they Gain Entrance and we still find them in the Spring! They travel in Groups of (1,000,000)!! Youroo!!
Right on youroo,,, the little Ba$tard$ are every where,,, I think I heard they are Japanese or Chinese ??? They are a different breed that the Lady bugs we use to have,,, and they can BITE !!! We are infested with Japanese Beetles this year !!!
You can buy stainless steel wire grid on ebay and cut to sizes needed to block heat outlets....use wire screen on inside of air intakes......reduce the use of insecticides and poisonous chemicals by keeping these critters out in the first place.
As to removing anode rod from hot water heater while filled with antifreeze......buy a PVC plug from any hardware store...it's a standard NPT thread size...or go big and buy brass...only 8 times the cost and works just as well as PVC.