Q: How does a Delta-Therm snow melting system work? A: The MI snow melting cable assembly or snow melting mat is embedded in concrete, sand, or asphalt. For best results embed the heating element within 3" of the pavement surface. Install the Delta-Therm DTC120-S, DTC120- PS, or MPS controller to monitor outdoor conditions and start or stop the snow melting system. When snow melting is called for the heating element will warm the pavement surface above 32°F and the snow will melt. The snow melting system will turn off automatically either using a 5-hour timing sequence (MPS) or based on outdoor weather conditions (DTC).