Hello, I sit corrected! No dip tube. 😀 This leaves little to check. I would confirm you’re getting 120 volts to it and using your ohm meter, check for any leaks to ground through the element. It does not sound like a bad thermostat, but a visual inspection of it to be sure there is no evidence of it getting wet or any electrical burn odor, (like burned Bakelite) would be nice too. I’m curious to know what you discover!