Quote Originally Posted by mudnut View Post
Just boil some water with the unit in it and watch it open, then close when you take it out. It just lets you know it won't get stuck as you can't pressurise the water to get the temp above 100 degrees.
If I understood you correctly, a pressurized test may be necessary to be conclusive?!

I have a pressure cooker, but I can't see what happens inside.
I guess, I can let the pressure vent quickly( and safely ) and see whether the thermostat stays stuck open afterwards?!