I have just come across this question (7th December 2020), so a bit late for this questioner. However, there might be others who have the same problem.
I have found the RMG 25 oil filled a great heater, and mine also just stoped working. When I removed the front cover, which contains the elecrics, I found the on/off switch had failed. No Dimplex spares available, so bought another rocker switch and mounted into the cover - now works!
John Catchpole
December 2020
Automatic Answer
While you wait for answers, we may have found some information which could help you.
howtomendit.com for free repair help, information and advice.
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