Hi @mturetsky ,
If it trips the breaker when the element is being powered on it indicates that there may be excess current flowing either due a faulty heater element or to a lesser extent moisture in the control board or problems with the electrical wiring in the cabinet.
First check that no other appliance is plugged into the same circuit fed by the breaker and is in use at the same time, as apparently the smoker requires a lot of current when the heater is turned on and this may be too much for the circuit breaker and it will trip. Perhaps try plugging in an electric kettle (these are usually 1200-2000W) in place of the smoker and check if that also trips the breaker when turned on.
If it also trips the breaker then there may be a problem with the breaker or the number of outlets connected to that particular breaker and what is connected to them.
If it doesn’t trip the breaker then use a DMM’s (digital multimeter) Ohmmeter function, to check that the smoker’s heater element is OK. Test it out of circuit i.e. disconnect it from the wiring harness in the cabinet, to measure what the resistance of the element is (I don’t know what it should be) and that it is not short circuit. Also test that the wires to the element aren’t shorting out to the cabinet by testing between the cabinet (bright, clean, shiny metal connection point)and the element harness connections with the Ohmmeter.
Here are the product manual and an electrical replacement manual for the appliance (I think they are the correct ones), that may help.