Is your electric fireplace starting to come on and then shuts off immediately? If so I had this problem a few months ago. There is a high temp sensor in the electric heating unit that would shut the fireplace down immediately after turning it on. It apparently had clogged up with something which I couldn't see when I removed it. I just blew it out air compressed air, reinstalled it and it worked fine.
If you go to the manufacturer's web site they have very detailed instructions on how to remove the heating element.
2006 GMC 2500HD CCSB 4x4 Duramax/Allison, Titan 52 gallon fuel tank, Prodigy Controller, B&W Companion Hitch
2010 Jayco Designer 35RLTS, Cummins/Onan RV QG 5500 EVAP, Progressive Industries EMS-PT50C, TST Systems 507 TPMS, RV Flex Armor Roof