Hi - we have recently had new panel heaters installed in a building at work (Dimplex PLX200E) and some un tech savvy colleague has activated the PIN lock on it and doesn't know how (or hence the PIN) hence the temp can't be adjusted and only "boost" is available. I've checked the manual and no joy. Popping the battery out of the control module resets the date but not the PIN! Any ideas? Thanks.