Space heaters are a type of heating device that is used to warm up a room or area. They come in a variety of shapes and sizes, and can be powered by electricity, gas, or oil. The three crossword solutions for the term SPACE HEATER are SUN (3 letters), NOVA (4 letters), and SOL (3 letters). SUN is an acronym for 'Standard Unit of Natural Energy, ' which is a unit of measurement for energy output from a SPACE HEATER. NOVA is a type of SPACE HEATER that uses natural gas as its fuel source. SOL is an acronym for 'Solar-Powered HEATER, ' which is a type of SPACE HEATER that uses solar energy to generate heat.