I've been running my WG for about 7 years, ad the center plug is bairly holding together. I've read a couple of threads about people replacing, and they seemed to imply it was important. Can someone help me understand what the importance of the center plug is? SImilar question, what is the EPA plug all about? Also, I seem to be having trouble keeping the thing going this year. Is there rule of thumb, or other way to know when the the fan is getting weak? I suspect it as a problem, but having a hard time telling for sure. Is there a cheaper way to get the fan than from AHS?