28: Royalstar RSD- 18 Fault code E0: No cooker or cooker is not suitable for E 1: Internal circuit system fault E2: sensor open circuit or short circuit E3: high voltage protection E4: low voltage protection E5: air combustion or furnace surface temperature is too high E6: internal temperature is too high jc Check the temperature sensor and its accessories. . . . . . . . . . . . . . . . . . . . . . . . . . . . .