Latest 40++ Fireplace Heating System. Procom heating pcs150t ventless fireplace insert thermostat control arched door, medium sunday living electric log set heater, insert fireplace heater with realistic flame and ember bed. Modern fireplaces vary in heat efficiency, depending on the design. You are here the system's fireplace boards are made of vermiculite; A fireplace or hearth is a structure made of brick, stone or metal designed to contain a fire.