One thing you can attempt to do is relocating the EdenPURE GEN4 A4428 heater to an interior wall within the room it is located.
Furthermore, the EdenPURE GEN4 Model A4428 heater was developed to provide supplemental heating to your living area in conjunction with another heat source such as a fireplaces or boilers. In addition, tile, cement and other similar floor types are porous surfaces and thus, tend to absorb a lot more heat. Therefore, the time needed to heat the room will take much longer.
Finally, if insulation in your room is lacking or there are a lot of windows, it won’t retain the heat as efficiently.