I bought an Intex sand filter second hand and it worked great for two years. As I'm setting it up this year, I find that I can't get it to power on. I've replaced the GFCI plug with a regular style three prong thinking maybe that might have gotten corroded after sitting out for that long. Nope. Still no power. What else could it be? Should I try to replace the three way switch? I bought a cheap cartridge filter to get me by for now but this means I cannot use the salt chlorinator I was planning on getting.