1. Thermal conduction - heat is transferred to the glass through physical contact of lower surface of the glass and the ceramic rollers in the glass tempering furnace. During the heating process, it is critical to maintain the temperature stability on the ceramic rollers. When customers are going to buy glass tempering furnaces, they shall pay special attention on certain technical specifications such as whether the ceramic roller temperature is adjustable, or if each and every spot on a roller maintains a constant temperature.

2. Thermal radiation - the heating elements in the glass tempering furnace transfers heat to the glass through thermal radiation. To precisely control the thermal radiation is the key technology that ensures the even heating. However, as the Low-E surface coating of the glass reflects radiation heat in different degrees, maintaining the precision of temperature control for low-E glass has been a big challenge.

3. Convection - heat is transferred to the glass through forced convection of heated air in the glass tempering furnace. Regardless the type of glass under process, heated air molecules will transfer heat to the glass through forced convection. Because of that, convection heating is effective for all types of glass with heating rate faster than thermal radiation method.