HM DO DeLonghi HS15F Safe Heat Convector Heater DeLonghi HS15F Safe Heat Convector Heater. DeLonghi Convection Heater HS15F features a silent fan. This superior convection system with internal fan delivers heat efficiently and produces up to 35 percent faster heating power. The units unique design allows for rapid heat convection. Dual heat flow settings lets you regulate the output of warm air. Adjustable thermostat provides energyefficient operation by letting you set the desired level of comfort. This unit has a PTC Thermal cut off to ensure product safety. If the unit becomes warm it automatically turns off no need to worry about overheating. You can easily determine that your heater is on by the power indicator lights and you will never have to walk into a cold room again with the antifreeze setting. The antifreeze setting automatically turns on the heater when the room temperature dips to 44 degrees Fahrenheit.