This excerpt from the user's manual can explain the problem of your switch.
"... This is normal and does not mean that the oven is defective. Leave the oven empty for 20 minutes in the broil position and then in convection mode (250°C) before using the oven for the first time. After 1 second, the default value appears on the display. If you do not want to change anything, press to exit the change mode. Skip this step if it is not necessary...."
ARTHUR MARTIN EMS2840, EMS2800, EMS28030, EMS28060, EMS28090, EMS280120, EMS2840S, EMS28400, EMS284035, EMS284070, EMS2840105, EMS2840140
Manufacturer's part price is £10.91 Discount for bulk (starting at 10 units), £10.55 per unit
This manufacturer part is recomended by ARTHUR MARTIN, which gives it a 10/10 rating.
This spare part is recommended for your ARTHUR MARTIN EMS2840 microwave oven .
All spare parts are new and come with a 1 year warranty
① Carefully check your ARTHUR MARTIN microwave oven's product number
② Start search
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