barrytm had a good suggestion; accumulated moisture from smoking or just a damp humid environment can do it.  If using an extension cord, try plugging in direct; cords laying on the ground can and do leak.  You can also try plugging in another device with a heating element into the same outlet: toaster oven, hair dryer, something with a similar wattage and amp draw and see what happens. It is possible that the gfci has gone bad. I use my smokers on a non-gfci outlet with no problems. But I need to say or warn that this is not truly wise even if the outlet is grounded.

If your smoker trips a gfci in a different location, your smoker wiring it likely the culprit. And electrician or appliance repair person can fix this. If only one circuit is affected, the gfci is likely bad. Call an electrician.  Be safe.

Hi everybody-my model 1 is tripping my gfci switch.. is there a way to check the heater element without removing it from the unit?

Welcome from Delaware, Timbo.   Glad to hear the ribs turned out great -- ribs are a good choice for the first smoke!  Cheers

Welcome Timbo from SE Arizona. Good to hear the ribs turned out great.

It seems like the original instructions with my smoker talked about cleaning the racks.  I read an article about the most successful BBQ joints in Texas.  The one thing that set them apart was cleaning the nastiness from the inside of the smokers on a regular basis.