While you wait for answers, we may have found some information which could help you.
Click here for Light Small ThermostatLight not working?
Faulty lights on Dimplex mk11?
Looking for reset button on dimplex convector heater DX25F10?
Dimplex 403BT convector heater?
How to change LED driver on Dimplex fire?
Dimplex Optiflame X1S Series B stopped working?