When i plug my Dimplex 403BT convector heater in the the power light comes on and
the lcd screen flashes red on and off with just a blank screen . unable to select any mode no matter which button i press also will not switch off on on/off button.
hope you can help otherwise will have to return it !
Regards
David

David, December 2022

Sounds like it THINKS it has overheated. Possible overheat sensor failure
You talk about returning it. One assumes it's not very old and is still under warranty. If so why would you risk invalidating the warranty by fiddling?

Djrj, December 2022