Your igniter is bad or arcing when the lights are flashing

Remove front grille by taking out two screws at lower right and left front sides of stove. slightly pull botom front of grille toward you and lift up and off. Look for two red wires going into burner chamber, the wires will be incased in a gray plastic sheath as they enter chamber. Push on buton like you are trying to start the heater. While it is going through start up process hold the gray plastic sheath with two fingers and see if the sheath does not get warm in a short period of time the igniter is bad and will need to be replaced. This can be cause by water getting into the burner chamber and causing the igniter to crack.