I just did this to my Vevor single burner, I let it air drey for 48hrs, then put the whole thing in an oven at 170 degrees for six hours. Then in the forge I did 30 seconds. shut it off and steam was escaping, then 3 min at low setting, let cool, Then 5 min, let it cool then 30 minits,close it up with brick and leave it until tomorrow. HERE IS THE WEB PAGE i WAS ON FROM VEVOR.
https://www.google.com/search?client=firefox-b-1-d&q=how+long+to+leave+ceramic+cement+dry+before+heating&udm=50&fbs=ADc_l-aN0CWEZBOHjofHoaMMDiKp9lEhFAN_4ain3HSNQWw-mMahSc1lZanrXzlAC79HZDR-SrTbKT4KCgY-ynec2PlWUWbNJb8kZO_S0WskcWb425IUurXPsS3baqpOhryX3FAmVCvf447Q26AqAdvDo-qkveDcM1u-ADeGGiGL1ToH8d2ejXC4V3g7L_IA_PUoosu1Oo8L4aQM9HZihZy3ucdvE5w0Tg&aep=10&ntc=1&mstk=AUtExfBVWl82m7uESCPyRdtlL5vmHcr6RYKgC2xpnpjxJhyqOOR8gMMF5Ct2G9tO9TSe6gNJrrA4DUeyzEW9fbUI7j2DectQ6tM-5q3BVfJx8PtIRi_yIzNU8xOnbDaaRx1Jz88ravTRVqc9P8gYXmCv9tLvBV0BRpZ44Mj6Fo-fuMvkoA77ZW2aA8YoRtF73NvJNQYxLZzB15SDyWzIYDnDDpp_bTHTMWPsqAEgdsNNrQIdVeNB_KBdTjm2LxeeU48Wwa8cDwghGe4nMVBag1prQNB8BbuaZQYftmOXB8-xmlW7xIGA0llekAC3_YihA-eMDYyGkgXsDhMfZw&aioh=3&csuir=1&mtid=0eAMaqSBM43qmLQP78yboQQ