What is this?

[pwven]

If you stand in front of the smoker and open the smoker door, on the back pannel more or less in the center but more to the left there is a bottom type unit installed. I think it is electrically connected.
My question is what is this unit? What is its purpose? and how does it work?

I have not opened the back yet but I am planning to install a second 500 watt element. Will this unit affect the second element in any way?

[tskeeter]

The button you are seeing is a temperature sensor.

[Habanero Smoker]

If you have the original model, that is a high temperature sensor that will shut of power to the original element once the cabinet gets too hot. The old cutoff temperature was 320°F. The later models; manufactured later than 2010 or there about would cut off around 300°F; but there is a 40°F, either way. So it could be higher or lower.

If you install separate wiring for the second element, if the high temperature sensor is tripped it will shut down the power to the original element, but the second element will continue to function. If you use piggyback wiring as TedEbear wired his, when the high temperature sensor shuts down both the original element, and  the second element. Having both shut off could be a safety feature. But if the sensor does not reset, you don't have any heating element to cook with. If you wire the elements separately, the second element will continue to work. Either way you wire, the best safety feature to have is a PID, or some other temperature controller.

[Gafala]

I agree with Habanero, PID is the best way to go, I did and have had no issues.

[pwven]

If you have the original model, that is a high temperature sensor that will shut of power to the original element once the cabinet gets too hot. The old cutoff temperature was 320°F. The later models; manufactured later than 2010 or there about would cut off around 300°F; but there is a 40°F, either way. So it could be higher or lower.

If you install separate wiring for the second element, if the high temperature sensor is tripped it will shut down the power to the original element, but the second element will continue to function. If you use piggyback wiring as TedEbear wired his, when the high temperature sensor shuts down both the original element, and  the second element. Having both shut off could be a safety feature. But if the sensor does not reset, you don't have any heating element to cook with. If you wire the elements separately, the second element will continue to work. Either way you wire, the best safety feature to have is a PID, or some other temperature controller.

Thanks for the detailed feedback. I am using a PID controller that will control both elements. Will open my smoker next week and install the second element. My PID controller works really well.