While you wait for answers, we may have found some information which could help you.
Click here for Replaced Weeks AirGlen Dimplex Oil Filled Heater OFC2000 2KW?
Fix my oil filled heater?
Low pressure below 1, Lockout on. won't rest?
vonhaur Dragan 2500w oil electric heater no power?
What size spanner to free rad bleed valve?
How can I mend my Hyundai oil filled radiator?