I'm sorry for your loss.This is a terrible thing to happen and in the interest of preventing it from happening to someone else I wonder if this heater was plugged into a separate thermostat (not one that is built into the heater) and if so what kind. As far as the 98 degree temp I wonder what kind of thermometer it was. Did it have a probe on the heat source or was it a stick on thermometer mounted to the side of the enclosure or what. My room heater started running too hot at the end of the winter and I had to throw it away. I will have to buy a new one for this winter. If you could give us the specifics of the equipment that you were using maybe others could benefit from the info.