Checked Convection Oven unit limit closed called mfg spoke to Jeff d I''d if contactor not pulling in two orange leads won''t tell computer to heat. checked voltage at contact coil no dc current present. dc power supply is good. not getting voltage from relay board. controller is calling for heat spending current to relay board. relay board not sending current to dc power supply. will obtain part and return. unit down needs part. blogger. 6/12/18 installed new board and tested unit came on and preheated to set temp and cycled found burnt diodes on old board. unit went into cycle unit is operational job complete.